Pharmaceutical costs in obese individuals: comparison with a randomly selected population sample and long-term changes after conventional and surgical treatment: the SOS intervention study.

Background: Obesity is associated with increased morbidity rates and pharmaceutical costs. To what extent various medication costs are affected by intentional weight loss is unknown.

Methods: A cross-sectional comparison of the use of prescribed pharmaceuticals was conducted in 1286 obese individuals in the Swedish Obese Subjects (SOS) intervention study and 958 randomly selected reference individuals. Medication changes for 6 years after bariatric surgery were evaluated in 510 surgically and 455 conventionally treated SOS patients.

Results: Compared with the reference group, obese individuals were more often taking diabetes mellitus, cardiovascular disease, nonsteroidal anti-inflammatory and pain, and asthma medications (risk ratios ranging from 2.3-9.2). Average annual costs for all medications were 1400 Swedish kronor (SEK) (US $140) in obese individuals and 800 SEK (US $80) in the reference population (P<.001). Average yearly medication costs during follow-up were 1849 (US $185) in surgically treated patients (weight change -16%) and 1905 SEK (US $190) in weight-stable conventionally treated patients (P =.87). The surgical group had lower costs for diabetes mellitus (difference: -94 SEK/y (-US $9]) and cardiovascular disease medications (difference: -186 SEK/y (-US $19]) but higher costs for gastrointestinal tract disorder (difference: +135 SEK/y [US $13]) and anemia and vitamin deficiency medications (difference: +50 SEK/y [US $5]).

Conclusions: Use and cost of medications are markedly increased in obese vs reference populations. Surgical obesity treatment lowers diabetes mellitus and cardiovascular disease medication costs but increases other medication costs, resulting in similar total costs for surgically and conventionally treated obese individuals for 6 years.