The impact of chronic obstructive pulmonary disease and obesity on length of stay and cost of spine surgery

BACKGROUND: Chronic obstructive pulmonary disease (COPD) and obesity may be more common among spine surgery patients than in the general population and may affect hospital cost. MATERIALS AND METHODS: We retrospectively studied the prevalence of COPD and obesity among 605 randomly selected spine surgery inpatients operated between 2005 and 2008, including lumbar microdiskectomy, anterior cervical decompression and fusion and lumbar decompression and fusion patients. The length of hospital stay and hospital charges for patients with and without COPD and obesity (body mass index [BMI]≥30 kg/m(2)) were compared. RESULTS: Among 605 spine surgery patients, 9.6% had a history of COPD. There were no statistical difference in the prevalence of COPD between the three spine surgery groups. Obesity was common, with 47.4% of the patients having a BMI≥30 kg/m(2). There were no significant differences in obesity rates or BMI values between the three types of spine surgery patients. Obesity rates between patients with and without COPD were 62.1% vs. 45.9%, and were statistically different (P<0.05). Similarly, significant difference (P<0.01) in BMI values between COPD and non-COPD groups, 32.66±7.19 vs. 29.57±6.048 (mean ± std. deviation), was noted. There was significant difference (P<0.01) in cost between nonobese female patients without COPD and those with obesity and COPD in the anterior cervical decompression and fusion (ACDF) group. No association with increased hospital length of stay or cost was found in the other two types of spine surgery or in male ACDF patients. CONCLUSION: COPD and obesity seem to additively increase the length of hospital stay and hospital charges in ACDF female patients, an important finding that requires further investigation.