Risk factors of admission for acute colonic diverticulitis in a population-based cohort study: The North Trondelag Health Study, Norway

AIM: To assess risk factors of hospital admission for acute colonic diverticulitis. METHODS: The study was conducted as part of the second wave of the population-based North Trondelag Health Study (HUNT2), performed in North Trondelag County, Norway, 1995 to 1997. The study consisted of 42570 participants (65.1% from HUNT2) who were followed up from 1998 to 2012. Of these, 22436 (52.7%) were females. The cases were defined as those 358 participants admitted with acute colonic diverticulitis during follow-up. The remaining participants were used as controls. Univariable and multivariable Cox regression analyses was used for each sex separately after multiple imputation to calculate HR. RESULTS: Multivariable Cox regression analyses showed that increasing age increased the risk of admission for acute colonic diverticulitis: Comparing with ages < 50 years, females with age 50-70 years had HR = 3.42, P < 0.001 and age > 70 years, HR = 6.19, P < 0.001. In males the corresponding values were HR = 1.85, P = 0.004 and 2.56, P < 0.001. In patients with obesity (body mass index ≥ 30) the HR = 2.06, P < 0.001 in females and HR = 2.58, P < 0.001 in males. In females, present (HR = 2.11, P < 0.001) or previous (HR = 1.65, P = 0.007) cigarette smoking increased the risk of admission. In males, breathlessness (HR = 2.57, P < 0.001) and living in rural areas (HR = 1.74, P = 0.007) increased the risk. Level of education, physical activity, constipation and type of bread eaten showed no association with admission for acute colonic diverticulitis. CONCLUSION: The risk of hospital admission for acute colonic diverticulitis increased with increasing age, in obese individuals, in ever cigarette smoking females and in males living in rural areas.