OBJECTIVE

Mood difficulties are common among patients with diabetes and are linked to poor blood glucose control and increased complications. Evidence on psychological treatments that improve both mood and metabolic outcomes is limited. Greater self-compassion predicts better mental and physical health in both healthy and chronically ill populations. Thus, the purpose of this randomized controlled trial (RCT) was to evaluate the effects of self-compassion training on mood and metabolic outcomes among patients with diabetes.

RESEARCH DESIGN AND METHODS

This RCT tested the effects of a standardized 8-week mindful self-compassion (MSC) program (n = 32) relative to a wait-list control condition (n = 31) among patients with type 1 and type 2 diabetes. Measures of self-compassion, depressive symptoms, diabetes-specific distress, and HbA1c were taken at baseline (preintervention), at week 8 (postintervention), and at 3-month follow-up.

RESULTS

Repeated-measures ANOVA using intention to treat showed that MSC training increased self-compassion and produced statistically and clinically significant reductions in depression and diabetes distress in the intervention group, with results maintained at 3-month follow-up. MSC participants also averaged a clinically and statistically meaningful decrease in HbA1c between baseline and follow-up of >10 mmol/mol (nearly 1%). There were no overall changes for the wait-list control group.

CONCLUSIONS

This initial report suggests that learning to be kinder to oneself (rather than being harshly self-critical) may have both emotional and metabolic benefits among patients with diabetes.

Major depression is estimated to affect at least 12% of patients with diabetes (1), with subclinical mood symptoms and distress apparent in nearly one-third (31%) of those living with this chronic condition (2). In addition to predicting a higher negative affect, the emotional burden of distress about managing one’s diabetes may be a qualitatively different experience from depression per se (3,4). Although both distress and depression are linked to poor glycemic control, evidence suggests that distress rather than depression may be a better predictor of metabolic outcomes (3,5). Of note, given the scale and impact of mood disturbance among patients with diabetes, evidence for psychological interventions that successfully treat depression and distress and, ideally, concurrently improve metabolic outcomes is limited.

Several reasons exist to continue the search for psychotherapeutic interventions to improve mental and physical health outcomes among patients with diabetes. A meta-analysis of randomized controlled trials (RCTs) for treating depression in diabetes showed that psychotherapeutic treatments are moderately effective for depression and that cognitive behavior therapy (CBT) in particular had a small effect on glycemic control (6). Although the number and sample sizes of studies included in this meta-analysis were relatively small (10 of the 14 studies investigated samples ranging from 13 to 60 participants), a more recent study of 87 adults with depression and uncontrolled type 2 diabetes found that CBT focused on adherence and depression improved these outcomes as well as glycemic control (7). On the other hand, in their RCT, Hermanns et al. (8) found that diabetes-specific CBT reduced depression and distress in a mixed sample (n = 214) of patients with type 1 and 2 diabetes but had no between-group effect on HbA1c, and a large-scale meta-analysis and review showed no effects of psychological interventions on glycemic control among adults with type 1 diabetes (9). Overall, the wide variation in methodologies and inclusion criteria, including the fact that most trials also included other supportive treatments such as diabetes education alongside the intervention, means that drawing conclusions about the efficacy of current psychological treatment approaches and/or their metabolic effects remains difficult.

Given the prevalence and health-related implications of mood difficulties among patients with diabetes and the lack of conclusive evidence for current psychological interventions or their effects on glycemic indices, the search for behavioral interventions that can meet patient needs on a broad scale must continue. One promising approach to improving well-being in clinical settings is the practice of self-compassion, an ancient idea arising alongside research into the health benefits associated with mindfulness. Studies of mindfulness interventions among patients with diabetes have shown consistent improvements in psychological outcomes, including depression, but effects on metabolic control have been varied (10). Fundamentally, self-compassion–based treatments are based on the notion that significant portions of psychological distress are created by the tendency to be self-critical about actual or perceive failures. Self-compassion incorporates mindfulness as a core component (11) while also attempting to encourage a sense of common humanity (recognizing that everyone goes through difficult times) and self-kindness (responding to one’s suffering with gentleness and understanding instead of judgment and criticism). Unlike mindfulness, self-compassion directly trains the capacity for active soothing and self-comforting in times of suffering. Patients learn to treat themselves in the same way they might treat distress in a beloved other, providing gentle comfort and tending to their own needs for self-care.

For a patient population in which the relentless demand for healthy blood glucose control presents daily opportunities for failure and, thus, attacks on the self, the practice of self-kindness may reduce psychological suffering with subsequent, flow-on metabolic benefits. Evidence in both healthy and patient populations (12) has linked greater self-kindness with better mood, and a meta-analysis of nearly 80 studies has shown a large effect size (r = 0.47) in the relationship between self-compassion and well-being (13). Although evidence from diabetes is scanty, one study found that self-compassion predicted less diabetes-specific distress and buffered the link between diabetes distress and poor metabolic outcomes (5).

Drawing from studies that show that self-compassion can be increased through training (14), the current investigation tested whether an 8-week group-based self-compassion intervention would improve psychological and physical health outcomes among patients with diabetes. We expected that self-compassion would increase over the training period and that the training would reduce both depression and diabetes-specific distress in the intervention arm. We also expected that these gains would be sustained at 3-month follow-up and that self-compassion training would reduce HbA1c levels across the same time period.

This RCT contrasted a standardized mindful self-compassion (MSC) intervention with a wait-list (treatment-as-usual) control. Participants were 63 patients with either type 1 or type 2 diabetes. They were aged 18–70 years (mean 42.87, SD 14.30), fluent in English, and able to attend a minimum of six of eight scheduled treatment sessions. Exclusion criteria were self-reported inability to read and write English. Participants were recruited between July 2014 and September 2014 at three hospital sites in Auckland, New Zealand. Recruitment was through self-referral to the trial or following recommendations from a patient’s physician or diabetes nurse; the study was widely advertised through numerous local diabetes centers. All participants provided written informed consent.

Procedure

Participants in the intervention condition (n = 32) were assessed at baseline (T1), at week 8 (T2), and 3 months after training had concluded (T3). Participants in the wait-list control condition (n = 31) completed identical measurements at the same three time points. Each time they provided data, participants received $20 vouchers to cover the costs associated with traveling to laboratories for blood testing. Participants received an additional $20 voucher for each MSC session they attended to cover transportation and parking costs. Treatment groups began in August 2014 and were completed by October 2014.

Treatment Allocation

A trained researcher blind to the hypotheses and study design and without participant contact used randomization software to allocate treatment assignments. Patients were told that they would be participating in a program based on evidence that learning to treat oneself with kindness and understanding when faced with difficult feelings and circumstances could be good for mental and physical health. They were told that they might be allocated to either a skills training workshop or a wait-list control. No further information about the MSC program was provided.

Intervention

MSC is a protocol-standardized intervention aimed at increasing mindfulness and self-compassion and reducing the suffering associated with experiential avoidance (14). Sessions were delivered to groups of 8–12 people during eight weekly sessions, each lasting 2.5 h. Adherence to the standard MSC protocol was strict, without specific reference to diabetes as a particular source of suffering. The intervention was delivered by the first author, a New Zealand–registered health psychologist trained to teach the program according to manualized MSC protocols. Clinical supervision was conducted weekly through Skype conference with MSC trainers across the intervention period. All participants received a standardized e-mail 2 days after each weekly session that summarized the week’s teachings and encouraged them to practice what they had learned during the previous session.

The central components of MSC are formal meditation together with formal and informal self-compassion practices aimed at developing the cognitive, behavioral, and physical capacities to soothe and comfort oneself when distressed (see Supplementary Data).

Wait-list Condition

Participants in the wait-list control condition received medical treatment as usual.

Assessments

Age, sex, ethnicity, and health status were assessed through self-report, as were time since diagnosis and type of diabetes.

Outcome Measures

Self-compassion was assessed using the Self-Compassion Scale (SCS) (11), a 26-item, 5-point Likert scale questionnaire comprising positive subscales of self-kindness, common humanity, and mindfulness and negative subscales of self-judgment, isolation, and overidentification. Studies have demonstrated satisfactory psychometric properties (15). Factor analysis has confirmed the six-factor structure of the scale and the single higher-order component of self-compassion. Reliabilities for the aggregate total score in the current study were T1 = 0.91, T2 = 0.91, and T3 = 0.93.

Depression

Symptoms of major depressive disorder were assessed with the 9-item Patient Health Questionnaire (PHQ-9) (16). By using a 2-week time window, responders rated symptoms on a scale of 1 (not at all) to 4 (almost every day). A summed score was calculated. The PHQ-9 is widely used and has excellent psychometric properties. It was validated with patients with diabetes in both primary and specialized outpatient clinics (17). α-Reliabilities for the current study are T1 = 0.81, T2 = 0.87, and T3 = 0.85.

Diabetes-specific distress is a common condition and is consistently linked to poor biobehavioral disease management (18). The 17-item Diabetes Distress Scale (DDS) has a consistent factor structure and good internal reliability and validity (18). The DDS contains items from four established domains of diabetes-related distress: emotional burden, physician-related distress, regimen-related distress, and interpersonal-related distress. A total score is calculated, with a mean item score of ≥3 considered to be high distress and worthy of clinical attention; higher scores on the DDS have been associated with greater HbA1c (18). α-Reliabilities for the total scale are T1 = 0.87, T2 = 0.90, and T3 = 0.92.

Glycemic control (indicated by HbA1c values at the three time points) was assessed using values reported by Lab Tests Auckland Ltd., an accredited medical testing laboratory, by using the COBAS Integra platform (Roche Diagnostics). HbA1c reflects mean blood glucose levels over the previous 2–3 months and is the standard assessment of glycemia (19).

Sample Size Calculation

The sample size calculation, based on 2 (group) × 3 (time) mixed-model repeated-measures ANOVA, was estimated from a review and meta-analysis of psychological interventions among patients with diabetes (5) in which the effects of treatment on glycemic control were substantially smaller than the moderate effects found for depression. A priori analyses with an f effect size of 0.25 and α-probability of 0.05 suggested a minimum sample of 44 participants. Allowing for dropout and retention (20,21), 63 participants were recruited. The sample size calculations were performed with GPower 3.1 software.

Statistical Analyses

The Consolidated Standards of Reporting Trials (CONSORT) guidelines for randomized trials were followed, and intention-to-treat analyses were conducted with SPSS Statistics 20 software (IBM Corporation). Individual missing values were imputed by using the means of the relevant subscale for the SCS and DDS or the total scale mean for the PHQ-9. For missing HbA1c values (n = 6 of 189), the most recently recorded value was carried forward. For the four participants who withdrew from the study, measurements from the time point before withdrawal were carried forward for analysis, and all multivariate assumptions were met. As a further check, per-protocol analyses were conducted, revealing a very similar pattern of results for both biological and subjective outcomes. Independent samples t tests and χ2 analyses were used to test for possible group differences in demographic and clinical variables at baseline (T1).

A series of 2 (group) × 3 (time) mixed-model ANOVAs tested the expectations that 1) randomization to the self-compassion training would increase self-compassion as well as reduce depression, distress, and HbA1c relative to the wait-list control and 2) these gains would be maintained at 3-month follow-up. Effect sizes are reported as partial η2p2) coefficients. To further interpret any time-by-group interactions, a series of t tests examined possible differences between baseline and postintervention (T1 and T2), between postintervention and 3-month follow-up (T2 and T3), and between baseline and 3-month follow-up (T1 and T3).

Clinically Meaningful Improvement

Clinically meaningful improvements in outcomes were defined as reductions between T1 and T3 of 1) at least 5 points on the baseline PHQ-9 score (22), 2) at least 1 point on the DDS mean (23), and 3) at least 0.5% (5.5 mmol/mol) in HbA1c scores (24). χ2 analyses were used to test between-group differences in the proportion of participants showing clinically significant improvement.

Recruitment and Attrition

As indicated in the CONSORT diagram (Fig. 1), 84 patients indicated an initial interest in participation. Of these, 71 were randomized (15% noneligible), and 63 ultimately provided data for the study (32 in the MSC condition, 31 in the wait-list control [89% of eligible]). χ2 analysis showed no group differences in attrition: Of the 63 participants who provided baseline data, 4 withdrew (2 from each condition).

Figure 1

CONSORT diagram showing the flow of participants with diabetes through each stage of the MSC RCT.

Figure 1

CONSORT diagram showing the flow of participants with diabetes through each stage of the MSC RCT.

Baseline Characteristics

Table 1 provides an overview of the study sample, stratified by group. No differences were found between the two groups at baseline in demographic or diabetes-specific characteristics other than time since diagnosis. However, between-group differences were seen at baseline on psychological and clinical metrics; PHQ-9, DDS, and HbA1c scores were greater and SCS scores were lower in the MSC group than in the wait-list control group. A greater proportion of intervention participants had clinically significant diabetes distress, but no differences between groups were found in the proportion with clinically significant depression (Table 2). Because of these baseline differences, primary analyses were replicated by ANCOVA in which baseline values were covaried and T2 and T3 values entered as repeated measures. Results were essentially unchanged.

Table 1

Baseline characteristics of the sample

DemographicMSC (n = 32)Wait-list (n = 31)Total (n = 63)
Age (years) 42.16 (14.70) 46.65 (16.44) 44.37 (15.62) 
Sex, n (%)    
 Male 12 (37.50) 8 (25.81) 20 (31.75) 
 Female 20 (62.50) 23 (74.19) 43 (68.25) 
Ethnicity, n (%)    
 New Zealand European 20 (62.50) 26 (83.88) 46 (73.02) 
 Maori 1 (3.22) 1 (1.59) 
 Asian 2 (6.25) 3 (9.67) 5 (7.94) 
 Other Pacific 1 (3.12) 3 (4.76) 
 Other European 7 (21.88) 1 (3.22) 8 (12.70) 
Type of diabetes, n (%)    
 Type 1 26 (81.25) 20 (64.51) 46 (73) 
 Type 2 3 (9.37) 6 (19.35) 9 (14.3) 
 Type 2 on insulin 3 (9.37) 5 (16.13) 8 (12.7) 
Time since diagnosis (years)* 19.90 (13.58) 13.46 (9.94) 16.84 (12.32) 
DemographicMSC (n = 32)Wait-list (n = 31)Total (n = 63)
Age (years) 42.16 (14.70) 46.65 (16.44) 44.37 (15.62) 
Sex, n (%)    
 Male 12 (37.50) 8 (25.81) 20 (31.75) 
 Female 20 (62.50) 23 (74.19) 43 (68.25) 
Ethnicity, n (%)    
 New Zealand European 20 (62.50) 26 (83.88) 46 (73.02) 
 Maori 1 (3.22) 1 (1.59) 
 Asian 2 (6.25) 3 (9.67) 5 (7.94) 
 Other Pacific 1 (3.12) 3 (4.76) 
 Other European 7 (21.88) 1 (3.22) 8 (12.70) 
Type of diabetes, n (%)    
 Type 1 26 (81.25) 20 (64.51) 46 (73) 
 Type 2 3 (9.37) 6 (19.35) 9 (14.3) 
 Type 2 on insulin 3 (9.37) 5 (16.13) 8 (12.7) 
Time since diagnosis (years)* 19.90 (13.58) 13.46 (9.94) 16.84 (12.32) 

Data are mean (SD) unless otherwise indicated.

*Significant differences between groups, P < 0.05.

Table 2

Primary outcomes at T1, T2, and T3

MeasureT1T2T3
SCS* (range 0–5)    
 MSC 2.52 (0.57) 3.10 (0.50) 3.21 (0.72) 
 Wait-list 2.88 (0.60) 3.12 (0.64) 3.08 (0.59) 
PHQ-9* (range 0–27)    
 MSC 14.01 (4.52) 9.16 (6.50) 7.88 (4.62) 
 Wait-list 9.74 (6.06) 7.30 (5.02) 9.32 (6.50) 
DDS17** (range 0–6)    
 MSC 3.16 (0.88) 2.33 (0.86) 2.10 (0.84) 
 Wait-list 2.35 (0.63) 2.29 (0.85) 2.10 (0.89) 
Clinical    
 HbA1c*    
  MSC    
   mmol/mol 74.25 (15.11) 71.44 (18.34) 64.03 (16.25) 
   % 8.94 (1.38) 8.69 (1.68) 8.0 (1.49) 
  Wait-list    
   mmol/mol 64.06 (13.32) 66.03 (14.20) 62.32 (12.41) 
   % 8.01 (1.22) 8.19 (1.14) 7.85 (1.36) 
 Depressed, n (%)    
  PHQ ≥12    
   MSC 20 (62.5) 11 (34.4) 6 (18.8) 
   Wait-list 13 (41.93) 7 (22.6) 7 (22.6) 
 Distressed**, n (%)    
  DDS ≥3    
   MSC 16 (50.00) 8 (25.0) 0 (0) 
   Wait-list 3 (9.70) 6 (19.4) 0 (0) 
MeasureT1T2T3
SCS* (range 0–5)    
 MSC 2.52 (0.57) 3.10 (0.50) 3.21 (0.72) 
 Wait-list 2.88 (0.60) 3.12 (0.64) 3.08 (0.59) 
PHQ-9* (range 0–27)    
 MSC 14.01 (4.52) 9.16 (6.50) 7.88 (4.62) 
 Wait-list 9.74 (6.06) 7.30 (5.02) 9.32 (6.50) 
DDS17** (range 0–6)    
 MSC 3.16 (0.88) 2.33 (0.86) 2.10 (0.84) 
 Wait-list 2.35 (0.63) 2.29 (0.85) 2.10 (0.89) 
Clinical    
 HbA1c*    
  MSC    
   mmol/mol 74.25 (15.11) 71.44 (18.34) 64.03 (16.25) 
   % 8.94 (1.38) 8.69 (1.68) 8.0 (1.49) 
  Wait-list    
   mmol/mol 64.06 (13.32) 66.03 (14.20) 62.32 (12.41) 
   % 8.01 (1.22) 8.19 (1.14) 7.85 (1.36) 
 Depressed, n (%)    
  PHQ ≥12    
   MSC 20 (62.5) 11 (34.4) 6 (18.8) 
   Wait-list 13 (41.93) 7 (22.6) 7 (22.6) 
 Distressed**, n (%)    
  DDS ≥3    
   MSC 16 (50.00) 8 (25.0) 0 (0) 
   Wait-list 3 (9.70) 6 (19.4) 0 (0) 

Data are mean (SD) unless otherwise indicated.

*Significant differences between groups at baseline, P < 0.05.

**Significant differences between groups at baseline, P < 0.001.

Changes in Self-Compassion

The ANOVA showed a main effect of time (F[2,60] = 13.07, P < 0.001, ηp2 = 0.30) but not of group (F[1,61] = 0.02, P > 0.05); however, there was an interaction between time and group (F[2,60] = 0.06, P = 0.001, ηp2 = 0.21). Plot inspection, confirmed with t tests (Table 3), showed that self-compassion increased in the MSC group between T1 and T2, with gains maintained at T3. No changes were found in the wait-list control group at any time (Fig. 2).

Table 3

Results of t tests between T1 and T2, T2 and T3, and overall differences between T1 and T3 for MSC and wait-list control groups separately

MeasureT1 and T2DifferenceT2 and T3DifferenceT1 and T3Difference
SCS        
 MSC t(31) = 4.70** 0.58 (0.12) t(31) = 0.88 0.11 (0.14) t(31) = 5.10** 0.70 (0.14) 
 Wait-list t(30) = 1.93 0.25 (0.13) t(30) = −1.92 −0.24 (0.12) t(30) = 0.14 0.01 (0.10) 
PHQ-9        
 MSC t(31) = −3.85* −4.86 (1.27) t(31) = −0.95 1.3 (1.35) t(31) = −5.92** −6.14 (1.04) 
 Wait-list t(30) = −1.96 −2.44 (1.25) t(30) = 1.74 2.03 (1.17) t(30) = −0.38 −0.41 (1.10) 
DDS17        
 MSC t(31) = 4.56** 0.83 (0.18) t(31) = −1.12 −0.23 (1.18) t(31) = −7.23** −1.06 (0.15) 
 Wait-list t(30) = −0.36 −0.06 (0.17) t(30) = −0.90 −0.19 (0.21) t(30) = −2.11* −0.25 (0.20) 
HbA1c       
 MSC  t(31) = −1.47 −2.81 (1.91) t(31) = −3.63* −7.41 (2.04) t(31) = −4.65** −10.22 (2.20) 
  mmol/mol       
  % t(31) = −1.47 −0.26 (0.18) t(31) = −3.63* −0.68 (0.19) t(31) = −4.65** 0.94 (1.14) 
 Wait-list       
  mmol/mol t(30) = 1.58 1.20 (1.25) t(30) = −3.27* −3.71 (1.14) t(30) = −1.20 −1.74 (1.45) 
  % t(30) = 1.58 0.18 (0.11) t(30) = −3.27* −0.34 (0.10) t(30) = −1.20 −0.16 (0.13) 
MeasureT1 and T2DifferenceT2 and T3DifferenceT1 and T3Difference
SCS        
 MSC t(31) = 4.70** 0.58 (0.12) t(31) = 0.88 0.11 (0.14) t(31) = 5.10** 0.70 (0.14) 
 Wait-list t(30) = 1.93 0.25 (0.13) t(30) = −1.92 −0.24 (0.12) t(30) = 0.14 0.01 (0.10) 
PHQ-9        
 MSC t(31) = −3.85* −4.86 (1.27) t(31) = −0.95 1.3 (1.35) t(31) = −5.92** −6.14 (1.04) 
 Wait-list t(30) = −1.96 −2.44 (1.25) t(30) = 1.74 2.03 (1.17) t(30) = −0.38 −0.41 (1.10) 
DDS17        
 MSC t(31) = 4.56** 0.83 (0.18) t(31) = −1.12 −0.23 (1.18) t(31) = −7.23** −1.06 (0.15) 
 Wait-list t(30) = −0.36 −0.06 (0.17) t(30) = −0.90 −0.19 (0.21) t(30) = −2.11* −0.25 (0.20) 
HbA1c       
 MSC  t(31) = −1.47 −2.81 (1.91) t(31) = −3.63* −7.41 (2.04) t(31) = −4.65** −10.22 (2.20) 
  mmol/mol       
  % t(31) = −1.47 −0.26 (0.18) t(31) = −3.63* −0.68 (0.19) t(31) = −4.65** 0.94 (1.14) 
 Wait-list       
  mmol/mol t(30) = 1.58 1.20 (1.25) t(30) = −3.27* −3.71 (1.14) t(30) = −1.20 −1.74 (1.45) 
  % t(30) = 1.58 0.18 (0.11) t(30) = −3.27* −0.34 (0.10) t(30) = −1.20 −0.16 (0.13) 

Data are mean (SE) unless otherwise indicated.

*P < 0.05.

**P < 0.001.

Figure 2

Mean difference scores in outcome measures of self-compassion (A), diabetes distress (B), depression (C), and HbA1c (D) for each group between T1 and T2 (baseline and postintervention), T2 and T3 (postintervention and 3-month follow-up), and T1 and T3 (baseline and 3-month follow-up).

Figure 2

Mean difference scores in outcome measures of self-compassion (A), diabetes distress (B), depression (C), and HbA1c (D) for each group between T1 and T2 (baseline and postintervention), T2 and T3 (postintervention and 3-month follow-up), and T1 and T3 (baseline and 3-month follow-up).

Changes in Depressive Symptoms

The ANOVA testing for changes in depressive symptoms showed an effect for time (F[2,60] = 12.40, P < 0.001, ηp2 = 0.29). As with the SCS scores, there was no main effect for group (F[1,61] = 2.40, P > 0.05), but there was a significant time-by-group interaction (F[2,60] = 7.07, P < 0.05, ηp2 = 0.19). Plot inspection confirmed by t tests (Table 3) showed that the intervention reduced depression scores in the MSC group between T1 and T2, with results maintained at T3. There were no changes in depression scores in the wait-list control group between any time point (Fig. 2).

Changes in Diabetes Distress

The ANOVA showed effects for both time (F[2,60] = 27.30, P < 0.001, ηp2 = 0.48) and group (F[1,61] = 3.92, P = 0.05, ηp2 = 0.06) as well as an interaction between time and group (F[2,60] = 12.24, P < 0.001, ηp2 = 0.29). Plot inspection, confirmed with t tests (Table 3), showed that the intervention reduced distress in the MSC group between T1 and T2, with improvements maintained at T3. Although there were no changes evident in the wait-list control group between T1 and T2, there was an overall reduction in distress scores between T1 and T3 (Fig. 2).

Changes in HbA1c

Results showed an effect for time (F[2,60] = 13.25, P < 0.001, ηp2 = 0.31) but not group (F[1,61] = 2.66, P > 0.05). The general reduction in HbA1c over time was qualified by an interaction between time and group (F[2,60] = 5.1, P < 0.05, ηp2 = 0.15). Inspection of the interaction plot, confirmed by t tests (Table 3), showed that although HbA1c did not change between T1 and T2 in the MSC group, scores reduced by >10 mmol/mol (nearly 1%) between T1 and T3. There was no change overall between T1 and T3 for the wait-list control group (Fig. 2).

Clinically Significant Change

Analyses demonstrated group differences in the proportion of participants showing clinically meaningful improvement between T1 and T3. In the MSC group, 20 (62.5%) participants recorded a clinically meaningful decrease in PHQ-9 depression scores compared with 5 (16.1%) in the wait-list control group (χ2 [1, n = 63] = 12.28, P < 0.001, ϕ = −0.47). Equally, 15 (46.9%) participants in the MSC group recorded clinically meaningful reductions in distress compared with 3 (9.7%) in the wait-list control group (χ2 [1, n = 63] = 8.93, P < 0.05, ϕ = −0.41). For HbA1c, 21 (65.6%) participants in the MSC group recorded a clinically meaningful decrease compared with 9 (29%) in the wait-list control group (χ2 [1, n = 63] = 7.05, P < 0.05, ϕ = −0.37).

To our knowledge, this report represents the first investigation into the possible utility of self-compassion training in improving mood and metabolic outcomes among patients with type 1 and type 2 diabetes. As expected, the 8-week MSC intervention increased self-compassion, a finding consistent with a prior RCT of the MSC protocol and other evidence suggesting that self-compassion can be learned (14). The current study extends these findings to a diabetes population, a difficult-to-treat patient group among whom harsh self-criticism is not only common (25) but also a likely correlate of mood and behavioral self-management difficulties. As such, finding that the intervention showed the expected benefits in terms of reducing depression and diabetes-specific distress is important. Perhaps most notably and consistent with our final hypothesis, self-compassion training also reduced HbA1c, suggesting that the MSC intervention affected both subjective and objective metrics, an extension of most prior psychosocial RCTs among patients with diabetes (26).

Given the absence of compassion-specific studies among patients with diabetes, this discussion considers these findings in relation to prior studies that incorporated aspects of mindfulness or acceptance, a class of psychosocial intervention that may also engender compassion alongside acceptance of difficult thoughts and feelings (4,27). We consider possible explanations for the benefits of self-compassion, evaluate the clinical possibilities for compassion-based therapies in diabetes, and offer directions for future research and clinical practice.

First, the finding that the MSC program reduced depression adds to the overall evidence for psychosocial interventions among patients with diabetes (69) and is consistent with several mindfulness-based RCTs (4,20,21) and uncontrolled studies (28,29). However, although mindfulness is a foundation of MSC, self-compassion is broader in scope than mindfulness alone, concurrently emphasizing self-kindness (rather than self-criticism) and common humanity (compared with isolation), qualities also associated with well-being (13). A recent pilot study among breast cancer survivors (another group in which mood disorders are common) of an 8-week cognitively based compassion intervention also reported reduced depression after sessions emphasizing self-kindness and common humanity (30), providing preliminary evidence for the efficacy of this type of training.

Second, that the training reduced diabetes distress is likewise consistent with prior mindfulness interventions (4,20,21). Although diabetes-related topics were not explicitly referred to during the MSC program, all participants were patients with diabetes. As such, the emphasis on mindful acceptance of difficulty as being normal (i.e., “other people in my situation feel like this”) and active soothing of stressed or uncomfortable emotional states (“may I be kind to myself in this moment”) likely elicited diabetes-related thoughts, with the MSC practices then proving helpful in reducing the associated distress. This interpretation is consistent with the findings of Gregg et al. (4) in which mindfulness and acceptance training reduced difficult diabetes-related thoughts and feelings. In contrast, a problem-solving approach (i.e., attempting to solve the problems eliciting distress) largely failed to find between-group differences in distress (23).

Third, the current finding that the MSC training resulted in reduced HbA1c is among a very small number of psychosocial RCTs to record this critical result (4,8,9). Although the interaction between mental health and metabolic outcomes among patients with diabetes is complex (9) and the impact of depression reduction to improve glycemic control still controversial (31), these results are consistent with preliminary evidence from studies suggesting that psychological factors buffer biological systems from the negative effects of diabetes distress (5).

One possible explanation for this pattern of benefit is found in data regarding the physiological and autonomic processes believed to underlie self-compassion. It may be that actively soothing oneself when distressed reduces stress responses that are linked to blood glucose levels (32). Evidence suggests that brief self-compassion exercises reduce cortisol (33), and a greater ability to self-soothe has been linked to greater heart rate variability (34), a measure of autonomic flexibility. Furthermore, cross-sectional data show that self-compassion is associated with lower interleukin-6 (35), perhaps implying a link with inflammatory processes that, in turn, are also linked to both stress (36) and HbA1c (37).

Hence, although the current data are clearly preliminary and do not directly illuminate the mechanisms at play, they are consistent with the notion that self-compassion deactivates threat systems (associated with the release of cortisol and adrenalin) and activates the mammalian self-soothing system associated with the release of oxytocin and opiates (38). Thus, learning to be kinder to oneself when stress or suffering arises (i.e., active self-soothing in the face of stress and difficult emotions) may be linked to particular physiological processes that are in themselves linked to HbA1c.

Study Limitations and Strengths

These contributions noted, the data are limited in some important ways. First, the findings are generalizable only to those who volunteered for the RCT. Although attrition was low for a longitudinal study of this kind (20,21) no formal analyses of selectivity were possible, and larger, more representative trials are warranted.

Second, although participants were not recruited based on mood problems, more than one-half (52.38%) reported clinically significant depression and nearly one-third (30.16%) reported clinically relevant distress at baseline, rates notably higher than those reported among patients with diabetes in general (20). Consequently, it is possible that patients with more distress differentially volunteered for the trial and/or that benefits are more pronounced among people with greater levels of distress and depression (and poorer glycemic control). In addition, we note a failure of randomization with between-group baseline differences in the key clinical markers of depression, distress, and HbA1c as well as in self-compassion. Although the analytic approach should accommodate such differences, findings must nonetheless be interpreted with caution because they may be limited to those with more room to improve in terms of greater baseline levels of depression and distress, among whom higher HbA1c can be expected (2).

Finally, the absence of an active control group means nonspecific factors, including group support or simply meeting with a teacher and fellow patients with diabetes in a supportive way over a period of 8 weeks, may be responsible for the observed effects. Caution must therefore be applied in attributing these results to the effects of the MSC intervention specifically, and findings must again be considered preliminary. Notwithstanding these limitations, this first RCT of a stand-alone psychological intervention (i.e., without the inclusion of diabetes-specific education or material) found differences in both psychological and physiological metrics (HbA1c) in what is a typically hard-to-treat population.

Offsetting these limitations, however, is a low dropout rate (6.30%), which is unusual for distressed patients with diabetes where levels of ∼30% dropout are common (20,21,39). Participants were clearly motivated to attend the MSC sessions and to stay involved in the program until completion. Wait-list control participants were also motivated to attend sessions, with nearly two-thirds subsequently taking part in the MSC program immediately following the conclusion of the experimental protocol.

Future Directions

Living with diabetes involves relentless self-care responsibilities that can be understandably overwhelming for patients. Opportunities for negative self-evaluation and self-criticism of failures in diabetes self-management abound. Although some evidence exists for the effectiveness of mindfulness-based interventions in this patient group, developing the capacity to actively soothe and comfort oneself during suffering (i.e., self-compassion) may also be useful in mitigating the harmful effects of self-criticism. Such benefits might conceivably extend to other chronically ill populations in which issues with self-regulation and mood are common. Randomized trials with large sample sizes, an active control group, and longer-term follow-up of both psychological and metabolic outcomes using easily replicable protocols are needed.

In summary, these data show that a standardized, 8-week self-compassion intervention improves both mental health and metabolic outcomes in patients with diabetes. The increased capacity to be kind and understanding to oneself in the face of difficult feelings may be an important focus for training as part of reducing the suffering linked to depression and distress and improving the key clinical marker of effective diabetes management: HbA1c.

Clinical trial reg. no. ACTRN12615000946516, www.anzctr.org.au.

This article is featured in a podcast available at http://www.diabetesjournals.org/content/diabetes-core-update-podcasts.

Funding. This study was made possible with the support of the New Zealand Society for the Study of Diabetes and the New Zealand Diabetes Foundation.

Duality of Interest. No potential conflicts of interest relevant to this article were reported.

Author Contributions. A.M.F. contributed to the data research and writing of the manuscript. M.H.J. and N.S.C. contributed to the data analysis and review and editing of the manuscript. R.G.C. provided clinical supervision. A.M.F. is the guarantor of this work and, as such, had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Prior Presentation. Parts of this study were presented in abstract form at the 2nd International Conference on Mindfulness, Rome, Italy, 11–15 May 2016.

1.
Roy
T
,
Lloyd
C
.
Epidemiology of depression and diabetes: a systemic review
. J Affect Disord
2012
;142(Suppl.):S8–S21
2.
Anderson
RJ
,
Freedland
KE
,
Clouse
RE
,
Lustman
PJ
.
The prevalence of comorbid depression in adults with diabetes: a meta-analysis
.
Diabetes Care
2001
;
24
:
1069
1078
[PubMed]
3.
Snoek
F
,
Bremmer
M
,
Hermanns
N
. Constructs of
depression and distress in diabetes: time for an appraisal
.
Lancet Diabetes Endocrinol
2015
;
3
:
450
460
[PubMed]
4.
Gregg
JA
,
Callaghan
GM
,
Hayes
SC
,
Glenn-Lawson
JL
.
Improving diabetes self-management through acceptance, mindfulness, and values: a randomized controlled trial
.
J Consult Clin Psychol
2007
;
75
:
336
343
[PubMed]
5.
Friis
A
,
Johnson
M
,
Cutfield
R
,
Consedine
N
. Does kindness matter?
Self- compassion buffers the negative impact of diabetes-distress on HbA1c
.
Diabet Med
2015
;32:1634–1640
6.
van der Feltz-Cornelis
CM
,
Nuyen
J
,
Stoop
C
, et al
.
Effect of interventions for major depressive disorder and significant depressive symptoms in patients with diabetes mellitus: a systematic review and meta-analysis
.
Gen Hosp Psychiatry
2010
;
32
:
380
395
[PubMed]
7.
Safren
SA
,
Gonzalez
JS
,
Wexler
DJ
, et al
.
A randomized controlled trial of cognitive behavioral therapy for adherence and depression (CBT-AD) in patients with uncontrolled type 2 diabetes
[published correction appears in Diabetes Care 2016;39:1065–1065].
Diabetes Care
2014
;
37
:
625
633
[PubMed]
8.
Hermanns
N
,
Schmitt
A
,
Gahr
A
, et al
.
The effect of a diabetes-specific cognitive behavioral treatment program (DIAMOS) for patients with diabetes and subclinical depression: results of a randomized controlled trial
.
Diabetes Care
2015
;
38
:
551
560
[PubMed]
9.
Winkley
K
,
Ismail
K
,
Landau
S
,
Eisler
I
.
Psychological interventions to improve glycaemic control in patients with type 1 diabetes: systematic review and meta-analysis of randomised controlled trials
.
BMJ
2006
;
333
:
65
[PubMed]
10.
Noordali
F
,
Cumming
J
,
Thompson
JL
.
Effectiveness of mindfulness-based interventions on physiological and psychological complications in adults with diabetes: a systematic review
.
J Health Psychol
. 30 December
2015
[Epub ahead of print]. DOI:
[PubMed]
11.
Neff
K
.
The development and validation of a scale to measure self-compassion
.
Self Ident
2003
;
2
:
223
250
12.
Terry
ML
,
Leary
MR
,
Mehta
S
,
Henderson
K
.
Self-compassionate reactions to health threats
.
Pers Soc Psychol Bull
2013
;
39
:
911
926
[PubMed]
13.
Zessin
U
,
Dickhäuser
O
,
Garbade
S
.
The relationship between self-compassion and well-being: a meta-analysis
.
Appl Psychol Health Well-Being
2015
;
7
:
340
364
[PubMed]
14.
Neff
KD
,
Germer
CK
.
A pilot study and randomized controlled trial of the mindful self-compassion program
.
J Clin Psychol
2013
;
69
:
28
44
[PubMed]
15.
Neff
KD
.
The Self-Compassion Scale is a valid and theoretically coherent measure of self-compassion
.
Mindfulness
2015
;7:1–11
16.
van Steenbergen-Weijenburg
KM
,
de Vroege
L
,
Ploeger
RR
, et al
.
Validation of the PHQ-9 as a screening instrument for depression in diabetes patients in specialized outpatient clinics
.
BMC Health Serv Res
2010
;
10
:
235
[PubMed]
17.
Fisher
L
,
Skaff
MM
,
Mullan
JT
,
Arean
P
,
Glasgow
R
,
Masharani
U
.
A longitudinal study of affective and anxiety disorders, depressive affect and diabetes distress in adults with type 2 diabetes
.
Diabet Med
2008
;
25
:
1096
1101
[PubMed]
18.
Polonsky
WH
,
Fisher
L
,
Earles
J
, et al
.
Assessing psychosocial distress in diabetes: development of the diabetes distress scale
.
Diabetes Care
2005
;
28
:
626
631
[PubMed]
19.
Derr
R
,
Garrett
E
,
Stacy
GA
,
Saudek
CD
.
Is HbA1c affected by glycemic instability
?
Diabetes Care
2003
;
26
:
2728
2733
[PubMed]
20.
van Son
J
,
Nyklíček
I
,
Pop
VJ
, et al
.
The effects of a mindfulness-based intervention on emotional distress, quality of life, and HbA1c in outpatients with diabetes (DiaMind)
.
Diabetes Care
2013
;
36
:
823
830
[PubMed]
21.
Tovote
KA
,
Fleer
J
,
Snippe
E
, et al
.
Individual mindfulness-based cognitive therapy and cognitive behavior therapy for treating depressive symptoms in patients with diabetes: results of a randomized controlled trial
.
Diabetes Care
2014
;
37
:
2427
2434
[PubMed]
22.
Löwe
B
,
Unützer
J
,
Callahan
CM
,
Perkins
AJ
,
Kroenke
K
.
Monitoring depression treatment outcomes with the Patient Health Questionnaire-9
.
Med Care
2004
;
42
:
1194
1201
[PubMed]
23.
Fisher
L
,
Hessler
D
,
Glasgow
RE
, et al
.
REDEEM: a pragmatic trial to reduce diabetes distress
.
Diabetes Care
2013
;
36
:
2551
2558
[PubMed]
24.
Lenters-Westra
E
,
Schindhelm
RK
,
Bilo
HJG
,
Groenier
KH
,
Slingerland
RJ
.
Differences in interpretation of haemoglobin A1c values among diabetes care professionals
.
Neth J Med
2014
;
72
:
462
466
[PubMed]
25.
Basco
M
.
Perfectionism and diabetes care
.
Diabetes Spectr
1998
;
11
:
43
48
26.
Harkness
E
,
Macdonald
W
,
Valderas
J
,
Coventry
P
,
Gask
L
,
Bower
P
.
Identifying psychosocial interventions that improve both physical and mental health in patients with diabetes: a systematic review and meta-analysis
.
Diabetes Care
2010
;
33
:
926
930
[PubMed]
27.
Pauley
G
,
McPherson
S
.
The experience and meaning of compassion and self-compassion for individuals with depression or anxiety
.
Psychol Psychother
2010
;
83
:
129
143
[PubMed]
28.
Young
L
,
Cappola
A
,
Baime
M
.
Mindfulness based stress reduction: effect on emotional distress in diabetes
.
Pract Diabetes Int
2009
;
26
:
222
224
29.
Rosenzweig
S
,
Reibel
DK
,
Greeson
JM
, et al
.
Mindfulness-based stress reduction is associated with improved glycemic control in type 2 diabetes mellitus: a pilot study
.
Altern Ther Health Med
2007
;
13
:
36
38
[PubMed]
30.
Dodds
SE
,
Pace
TW
,
Bell
ML
, et al
.
Feasibility of cognitively-based compassion training (CBCT) for breast cancer survivors: a randomized, wait list controlled pilot study
.
Support Care Cancer
2015
;
23
:
3599
3608
[PubMed]
31.
Lustman
PJ
,
Clouse
RE
.
Depression in diabetic patients: the relationship between mood and glycemic control
.
J Diabetes Complications
2005
;
19
:
113
122
[PubMed]
32.
Surwit
RS
,
van Tilburg
MA
,
Zucker
N
, et al
.
Stress management improves long-term glycemic control in type 2 diabetes
.
Diabetes Care
2002
;
25
:
30
34
[PubMed]
33.
Rockliff
H
,
Gilbert
P
,
McEwan
K
,
Lightman
S
,
Glover
D
.
A pilot exploration of heart rate variability and salivary cortisol responses to compassion-focused imagery
.
Clin Neuropsychiatry
2008
;
5
:
132
139
34.
Porges
SW
.
The polyvagal perspective
.
Biol Psychol
2007
;
74
:
116
143
[PubMed]
35.
Breines
JG
,
Thoma
MV
,
Gianferante
D
,
Hanlin
L
,
Chen
X
,
Rohleder
N
.
Self-compassion as a predictor of interleukin-6 response to acute psychosocial stress
.
Brain Behav Immun
2014
;
37
:
109
114
[PubMed]
36.
Slavich
GM
,
Irwin
MR
.
From stress to inflammation and major depressive disorder: a social signal transduction theory of depression
.
Psychol Bull
2014
;
140
:
774
815
[PubMed]
37.
Kristiansen
OP
,
Mandrup-Poulsen
T
.
Interleukin-6 and diabetes: the good, the bad, or the indifferent
?
Diabetes
2005
;
54
(
Suppl. 2
):
S114
S124
[PubMed]
38.
Gilbert P, Irons C. Focused therapies and compassionate mind training for shame and self-attacking. In Compassion: Conceptualisations, Research and Use in Psychotherapy. Gilbert P, Ed. New York, Routledge, 2005, pp. 263–325
39.
van Bastelaar
KM
,
Pouwer
F
,
Cuijpers
P
,
Riper
H
,
Snoek
FJ
.
Web-based depression treatment for type 1 and type 2 diabetic patients: a randomized, controlled trial
.
Diabetes Care
2011
;
34
:
320
325
[PubMed]
Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered. More information is available at http://www.diabetesjournals.org/content/license.

Supplementary data