Adherence to a Mediterranean diet and health-related quality of life: a cross-sectional analysis of overweight and obese middle-aged and older adults with and without type 2 diabetes mellitus

The relationship between adherence to a Mediterranean diet (MedDiet) and health-related quality of life (HRQoL) is unclear, particularly in vulnerable older adults. This cross-sectional analysis explored the association between adherence to a MedDiet and subscales of HRQoL in two independent cohorts of overweight and obese middle-aged to older adults with and without type 2 diabetes mellitus (T2DM). Both cohorts were community-dwelling (T2DM aged ≥ 50 years; non-T2DM aged ≥ 60 years) with a BMI ≥ 25 kg/m2. Adherence to a MedDiet was assessed using the Mediterranean Diet Adherence Screener, and HRQoL was determined using the 36-item short-form health survey. Multiple regression analysis was used to examine the association between adherence to a MedDiet and HRQoL subscales. A total of 152 middle-aged to older adults were included (T2DM: n 87, 71·2 (sd 8·2) years, BMI: 29·5 (sd 5·9) kg/m2; non-T2DM: n 65, 68·7 (sd 5·6) years, BMI: 33·7 (sd 4·9) kg/m2). Mean adherence scores for the entire cohort were 5·3 (sd 2·2) (T2DM cohort: 5·6(sd 2·3); non-T2DM cohort: 4·9 (sd 2·0)). In the adjusted model, using pooled data from both study cohorts, adherence to a MedDiet was significantly associated with the general health subscale of HRQoL (β = 0·223; 95 % CI 0·006, 0·044; P = 0·001). Similar findings were also observed in the T2DM cohort (β = 0·280; 95 % CI 0·007, 0·054; P = 0·001). However, no additional significant associations between adherence to a MedDiet and HRQoL subscales were observed. We showed that adherence to a MedDiet was positively associated with the general health subscale of HRQoL in middle-aged to older adults with T2DM. However, larger longitudinal data in older adults with a wider range of adherence scores, particularly higher adherence, are required to better understand the direction of this relationship.