Morbidity characteristics related to cardiovascular outcomes in French Canadian Families of the Saguenay-Lac-Saint-Jean region of Quebec

BACKGROUND: The World Health Organization (WHO) recognizes cardiovascular diseases (CVD), such as high blood pressure (hypertension; HBP), coronary heart disease (e.g. myocardial infarction), cerebrovascular disease (stroke) and heart failure, as the major cause of death globally. Furthermore, CVD are multifactorial traits with a steeply rising prevalence worldwide, determined by a complex interplay of interactions between genome and environment, which renders their hereditary analysis a complicated task. Our previous studies in the founder population of French-Canadian families from the Saguenay-Lac-Saint-Jean (SLSJ) region of Quebec revealed the largest set of significantly linked loci to hypertension and its metabolic components [1, 2].  HYPOTHESIS AND OBJECTIVE: Since our preliminary findings suggest that early mortality from CVD has genetic and environmental factors, we hypothesize that our population will have distinct characteristics from diseases with and without fatal outcomes (FO and NFO, respectfully), especially in relation to CV cause. Our objectives are to analyze morbidity causes, their temporal characteristics and their clustering in the hypertensive families with or without obesity from the SLSJ region, using hospital, civic death registries and genealogical records from 1950 to the present. We want to describe and study FO and compare them to NFO.  RESULTS: In total, we identified 3,654 diagnosis from FO and NFO in 343 participating subjects. For FO, we report: (1) 299 participants suffered from diseases of the circulatory system with a grand total of 1,103 diagnosis, 555 outcomes and 247 first outcomes; (2) 333 of the participating subjects were affected by non-CV systems with a total of 1,536 diagnosis, 195 outcomes and 107 first outcomes; (3) all other diseases were responsible for a total of 81 diagnosis, 30 outcomes and 11 first outcomes in 62 of the participating subjects; and for NFO: (1) the circulatory system affected 105 of the participating subjects with a total of 156 diagnosis; (2) non-CVD, 53 of participating subjects with a total of 60 diagnosis; (3) all other diseases were found in 252 of participating subjects with a total of 718 diagnosis. For FO, 109 of 333 affected subjects by non-CVD and 58 of 62 by all other diseases had also a concomitant CVD. We were able to show characteristics from both FO and NFO. In both first outcomes and total outcomes, CVD predominated over non-CV and all other diseases. When examining CV co-affection with non-CV or all other diseases, 67.1% of our sample population was affected by CV FO. In fact, our sample showed a threefold risk increase in developing CVD (p<0.0001; χ2=1,575.348) when compared to the general population of SLSJ, while it diminished by half for non-CVD (p=0.0006; χ2=11.834). Finally, the relative risk for developing malignancies decreased by half in our sample in contrast to the same region.  CONCLUSION: This 11 year follow-up study provided a unique insight into affections for both FO and NFO. When looking at malignancies in conjunction with CVD, this risk grew twofold in our sample.

Keyphrases: Cardiovascular diseases, Outcomes, Diagnosis, First outcomes, Hypertension, Cancer, Diseases with mortality, Diseases without mortality, Hypertension, Cancer, Occurrences non fatales