The studies examined data in Taiwan’s Longitudinal Health Insurance Database, which contains data from one million randomly selected subjects from the National health Insurance Research Database.
For the urinary incontinence analysis, Hsiao-Jen Chung, MD, of Taipei Veterans General Hospital, and colleagues identified 1,943 subjects diagnosed with the condition from 1997 to 2001 and had no history of upper urinary stones or spinal cord injury. These subjects were matched with 9,715 age- and gender matched controls. All subjects were followed up until the end 2009, with a minimum follow-up of eight years. Upper urinary stones developed 407 (20.9%) of the study subjects compared with 1,088 (11.2%) of controls. In adjusted analyses, urinary incontinence was associated with a significant twofold increased risk of upper urinary stones.
For the chronic periodontitis study, the same team compared 16,292 individuals diagnosed with chronic periodonitis from 1997 to 2001 with 48,876 age- and gender-matched controls. The follow up was the same as in the urinary incontinence study.
Upper urinary stones developed in 1,761 (10.8%) of the study subjects versus 4,775 controls (9.8%). In adjusted analyses, chronic periodontitis was associated with a significant 14% increased risk of upper urinary stones.
The investigators advised that patients with urinary incontinence or chronic periodontitis be checked for urinary stones.