Out CKD Control with CKD Model 4 Control without CKD Control with CKD Gout but no CKD Gout plus CKD 1 3.36 1.62 3.21 3.24 1.58 2.99 3.48 1.67 3.44 0.02 0.01 0.04 <.0001 <.0001 <.0001 1 1.76 1.10 1.38 1.70 1.07 1.29 1.82 1.13 1.48 0.02 0.02 0.04 <.0001 <.0001 <.0001 1 3.35 3.24 3.47 0.02 <.0001 1 1.74 1.68 1.81 0.02 <.0001 1 1.99 1.85 2.14 0.04 <.0001 1 1.40 1.29 1.51 0.04 <.0001 1 1.69 1.65 1.74 0.01 <.0001 1 1.10 1.07 1.13 0.01 <.0001 Crude HR 95 CI Low Up SE P-Value Adjusted HR* 95 CI Low Up SE P-Value*Adjustments were made in these Cox models for gender, age, smoking and alcoholism-related diagnoses, hypertension, hyperlipidemia, atrial fibrillation and Charlson's co-morbidity index (CCI) score. To avoid double-counting (over-adjustment), in subjects with chronic kidney disease, CCI score did not consider chronic renal failure as a comorbidity. CVD cardiovascular disease; CI confidence interval; CKD chronic kidney disease. HR hazard ratio which was calculated by Cox proportional time-to-event survival analysis; SE standard error.Kok et al. BMC Cardiovascular Disorders 2012, 12:108 http://www.biomedcentral.com/1471-2261/12/Page 7 ofyears down to 8.77 in the age group of 80 years (Table 1). This difference of the prevalence of gout in different age group can be explained by the fact that subjects who live longer are less likely afflicted with gout problems or its related complications. The strengths of this study is using smoking-related diagnosis, alcoholism-related diagnosis, Charlson-Deyo comorbidity index score to avoid the occurrence of recall bias from interview-based or questionnaire-based study design [16,17]. Our results show that gout is an independent risk factor for CVD mortality. The relative risk for CVD mortality as the cause of death in the next five years is 1.71 with a narrow 95 confidence interval of 1.66 to 1.75. The crude hazard ratio for subsequent death from CVD in subjects with gout is 1.69 (95 CI, 1.65-1.74). After adjustment made for gender, age, smoking-related diagnosis, alcoholism-related diagnosis, hypertension, hyperlipidemia, atrial fibrillation and Charlson's comorbidity index score, the multivariable Cox regression analysis still shows a statistically significant hazard ratio of 1.10 (95 CI, 1.07-1.13). This confirms that gout alone modestly increases the risk for subsequent CVD mortality in the next five years. Review of the literature on the association between gout and CHD or CVD mortality discloses four relevant studies of heterogeneous study design and different follow-up time [3,5,19,20]. The Health Professionals Follow Up Study and the Multiple Risk Factor Intervention Trial included Caucasian male subjects only[5,19]. The HR for cardiovascular mortality in the latter trial was not statistically significant exhibiting an adjusted HR of 1.21 (95 CI, 0.99-1.49) [19]. A single institution observational study in Taiwan using health screening PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/25962748 program subjects shows that the adjusted HR for CVD death is 1.97 (95 CI, 1.08-3.59) in participants with gout [3]. This study had short follow up time (mean, 56 months) and did not make adequate adjustment for significant confounders such as medical comorbidities. A recently published study from Singapore which included only Chinese aged 45 to 74 years with gout has demonstrated an HR for CHD mortality of 1.38 (95 CI, 1.10 – 1.73) [20]. Nevertheless, this study I-CBP112 supplier necessitated the participants to recall a history of previously diagnosed gout as their stand.