Lifestyle Adherence and Metabolic Control in Adults with Type 2 Diabetes: Development of a Lifestyle Compliance Index

Background: Lifestyle modification is central to type 2 diabetes mellitus (T2DM) management, but adherence is difficult to assess in routine care. We developed a pragmatic Lifestyle Compliance Index (LCI) from routinely collected behavioral variables and examined its cross-sectional associations with cardio-renal-metabolic measures. Objectives: To describe the LCI, compare outcomes across adherence categories, evaluate adjusted associations, and quantify incremental discrimination for prevalent metabolic and renal abnormalities. Methods: Adults with T2DM attending a specialized outpatient diabetes clinic in Romania were assessed using a standardized clinical questionnaire and routine laboratory data. The LCI combined seven binary behaviors and graded physical activity (0–2 points; theoretical range 0–9). Group comparisons, unadjusted bivariate and adjusted multivariable regressions, false discovery rate correction, and stratified five-fold cross-validated logistic models were used. Results: Among 232 participants, 231 had a complete LCI; low, moderate, and high adherence included 84 (36.4%), 94 (40.7%), and 53 (22.9%) participants, respectively. Higher LCI scores were associated with lower adiposity, HbA1c, TyG index, triglycerides, creatinine, and SCORE2-Diabetes risk and with higher eGFR. In models adjusted for age, sex, and diabetes duration, each LCI point was associated with lower odds of obesity (aOR 0.749), elevated TyG index (0.757), albuminuria (0.716), reduced eGFR (0.802), and HbA1c ≥ 7% (0.833). Adding LCI improved cross-validated discrimination most for albuminuria (AUC 0.482 to 0.642), obesity (0.489 to 0.619), and elevated TyG index (0.524 to 0.646). The baseline albuminuria AUC was below chance, and the extended AUC remained modest. Conclusions: In this cross-sectional sample, higher self-reported lifestyle adherence was associated with a more favorable cardio-renal-metabolic profile. The LCI should be considered exploratory until validated against objective measures and tested in larger prospective populations.