Undetected and undiagnosed comorbidity in patients with obesity undergoing bariatric surgery—Results from the Berlin Bariatric Cohort study

The quality of general obesity management before bariatric surgery (BS) is rarely investigated. Inadequate information regarding undetected and undiagnosed comorbidities (UUCs) in individuals with obesity may influence the penetration, risks, and outcomes of BS. We conducted a cohort study involving a pre-specified medical check-up in a cooperation between a BS department and an outpatient medical centre. A total of 1068 patients (74.4% women) were enrolled in the study. The mean age was 42.1 years (standard deviation [SD] 11.9) and the mean body mass index (BMI) was 46.1 (SD 6.91). The onset of obesity occurred in 11.4% of patients during childhood, 47.2% during schooltime/adolescence, 41.4% in adulthood. Gender differences were observed: men had higher BMI, systolic blood pressure, and impaired metabolic state (including diabetes, dyslipidemia, and liver disease with p-values <.001 for all). Women had lower haemoglobin levels, impaired iron status, lower albumin levels (p < .001), and increased C-reactive protein levels (p < .05). The prevalence of UUC conditions (percentage of cases) was as follows: arterial hypertension, 53%; decreased cystatin C clearance, 57%; dyslipidemia, 41%; fatty liver, 40%; iron deficiency, 37%; diabetes mellitus, 34%; vitamin D deficiency, 32%; chronic pain syndrome, 23%; liver fibrosis, 12%; obstructive sleep apnea, 10%; and vitamin deficiencies (vitamin B₁₂, folic acid, vitamin K₁) <10%. Undiagnosed hypertension was more prevalent in younger women, and nutritional deficits were associated with high BMI in both genders. Older age and high BMI were associated with undiagnosed diabetes and decreased glomerular filtration rate in both genders, and with liver fibrosis in men. UUC are highly prevalent in individuals undergoing BS. A refined assessment is recommended to improve health conditions and outcome in these candidates.