The Relation between Changes in Vitamin D and Vitamin B12 Levels, Body Mass Index and Outcome in Methadone Maintenance Treatment Patients.

Patients' Body Mass Index (BMI) increase during methadone maintenance treatment (MMT), and both Vitamins D and B12 deficiencies may be associated with BMI. We studied the relations between BMI, these vitamins and treatment outcome in patients with opioid use disorder receiving MMT. Vitamin B12 levels were available for 272 patients and Vitamin D levels were available for 260 patients. Of those 112 and 80 respectively had two measures (at admission or thereafter, and while stabilized or after one year in treatment). Patients' BMI levels and long-term retention were analyzed. Vitamin B12 was lower in patients abusing cocaine/amphetamine on admission. Vitamin D did not change over time, but a significant weight gain could be observed in 38 patients whose vitamin D was elevated compared to 42 whose levels were not, (25.4 ± 4.8 to 28.8 ± 5.2 vs. 24.3 ± 3.7 to 25.5 ± 4.0, p(Time) < 0.0005, p(Group) = 0.03, p(interaction) = 0.02). BMI changes correlated with vitamin D levels change (r = 0.26, p = .04). Longer cumulative retention was observed among the elevated vitamin D group (8.1 years, 95% CI 6.3-9.8) in comparison with the non-elevated group (4.8y 95% CI 3.6-6.1, Kaplan Meier, p = .02). Stimulants misuse was associated with low B12 levels. Vitamin D elevation is associated with weight gain and longer retention in treatment.