Long term effects of low protein diet on depressive symptoms and quality of life in elderly Type 2 diabetic patients

Objectives: The long term effects of a low protein diet (LPD) on depressive symptoms and the quality of life in elderly Type 2 diabetic are unclear. Methods: 38 elderly Type 2 diabetic patients with CRD (Stage 3 - 4) were enrolled in the study. After 4 weeks on a normal protein diet regimen (NPD) providing 1.0 g/kg per day, all participants were assigned for 30 months, randomly, to a LPD (0.7 g/kg per day), either 7 days a week (LPD 7/7) or 6 days a week (LPD 6/7). Mini mental state examination (MMSE), activities daily living (ADL), cumulative illness severity (CIRS-IS), geriatric depression scale (GDS-15) and short-form healthy survey (SF-36) were evaluated every 3 months. Results: Before the LPD regimen creatinine clearance (CrCl), MMSE, ADL, CIRS-IS, GDS-15 and SF-36 were similar in both LPD 7/7 and LPD 6/7 groups. After 30 months, the mean GDS-15 increased significantly more in LPD 7/7 group than in LPD 6/7 group (p <0.05). Both mean SF-36 MCS and SF-36 PCS were decreased significantly more in LPD 7/7 group than in LPD 6/7 group (p <0.05). After 30 months, the decline in CrCl observed was similar in LPD 7/7 and LPD 6/7 groups (2.77 ± 0.3 and 2.84 ± 0.3 ml/min/year, respectively). Conclusion: In elderly Type 2 diabetic patients, long term effects of LPD 6/7 regimen in comparison to LPD 7/7 are associated with a similar decline in CrCl, but with decreased depressive symptoms and a better quality of life.