title: The comparative risk of new-onset diabetes after prescription of drugs for cardiovascular risk prevention in primary care: a national cohort study.
abstract: OBJECTIVE
  Recent studies suggest that statins increase the risk of subsequent diabetes with a clear dose response effect. However, patients prescribed statins have a higher background risk of diabetes. This national cohort study aims to provide an estimate of the comparative risks for subsequent development of new-onset diabetes in adults prescribed statins and in those with an already higher background risk on cardiovascular risk-modifying drugs and a control drug.
  
  
  METHODS
  Longitudinal cohort study.
  
  
  METHODS
  Use of routinely collected data from a complete national primary care electronic prescription database in New Zealand.
  
  
  METHODS
  32 086 patients aged between 40 and 60 years in 2005 were eligible and assigned to four non-overlapping groups receiving their first prescription for: (1) diclofenac (healthy population) n=7140; (2) antihypertensives thought likely to induce diabetes (thiazides and β-blockers) n=5769; (3) antihypertensives thought less likely to induce diabetes (ACE inhibitors, angiotensin II receptor blockers, calcium channel blocker) n=6565 and (4) statins n=12 612.
  
  
  RESULTS
  Numbers of first metformin prescriptions were compared between these groups from 2006 to 2011.
  
  
  RESULTS
  Patients prescribed statins have the highest risk of receiving a subsequent metformin prescription (HR 3.31; 95% CI 2.56 to 4.30; p<0.01), followed by patients prescribed antihypertensives thought less likely to induce diabetes (HR 2.32; 95% CI 1.74 to 3.09; p<0.01) and patients prescribed antihypertensives thought more likely to induce diabetes (HR 1.59; 95% CI 1.15 to 2.20; p<0.01) in the subsequent 6 years of follow-up, when compared to diclofenac.
  
  
  CONCLUSIONS
  These findings further support the link between statin use and new-onset diabetes and suggest that the understanding of diabetes risk associated with different antihypertensive drug classes may bear practice modification. This provides important information for future research, and for prescribers and patients when considering the risks and benefits of different types of cardiovascular risk-modifying drugs.
authors.affiliation: Department of Public Health and General Practice, University of Otago, Christchurch, New Zealand.
authors.forename: Olivia
authors.initials: O
authors.lastname: Currie
authors.forename: Dee
authors.initials: D
authors.lastname: Mangin
authors.forename: Jonathan
authors.initials: J
authors.lastname: Williman
authors.forename: Bianca
authors.initials: B
authors.lastname: McKinnon-Gee
authors.forename: Paul
authors.initials: P
authors.lastname: Bridgford