Is poor oral health a risk marker for incident cardiovascular disease hospitalisation and all-cause mortality? Findings from 172 630 participants from the prospective 45 and Up Study

Abstract

Objective: To investigate the relationship between oral health and incident hospitalisation for ischaemic heart disease (IHD), heart failure (HF), ischaemic stroke and peripheral vascular disease (PVD) and all-cause mortality.

Design: Prospective population-based study of Australian men and women aged 45 years or older, who were recruited to the 45 and Up Study between January 2006 and April 2009; baseline questionnaire data were linked to hospitalisations and deaths up to December 2011. Study exposures include tooth loss and self-rated health of teeth and gums at baseline.

Setting: New South Wales, Australia.

Participants: Individuals aged 45-75 years, excluding those with a history of cancer/cardiovascular disease (CVD) at baseline; n=172 630.

Primary outcomes: Incident hospitalisation for IHD, HF, ischaemic stroke and PVD and all-cause mortality.

Results: During a median follow-up of 3.9 years, 3239 incident hospitalisations for IHD, 212 for HF, 283 for ischaemic stroke and 359 for PVD, and 1908 deaths, were observed. Cox proportional hazards models examined the relationship between oral health indicators and incident hospitalisation for CVD and all-cause mortality, adjusting for potential confounding factors. All-cause mortality and incident CVD hospitalisation risk increased significantly with increasing tooth loss for all outcomes except ischaemic stroke (ptrend<0.05). In those reporting no teeth versus ≥20 teeth left, risks were increased for HF (HR, 95% CI 1.97, 1.27 to 3.07), PVD (2.53, 1.81 to 3.52) and all-cause mortality (1.60, 1.37 to 1.87). The risk of IHD, PVD and all-cause mortality (but not HF or ischaemic stroke) increased significantly with worsening self-rated health of teeth and gums (ptrend<0.05). In those reporting poor versus very good health of teeth and gums, risks were increased for IHD (1.19, 1.03 to 1.38), PVD (1.66, 1.13 to 2.43) and all-cause mortality (1.76, 1.50 to 2.08).

Conclusions: Tooth loss and, to a lesser extent, self-rated health of teeth and gums, are markers for increased risk of IHD, PVD and all-cause mortality. Tooth loss is also a marker for increased risk of HF.

Keywords: cardiovascular disease epidemiology; mortality; oral health.

Figure 1

Age-standardised rates per 1000 person-years of all-cause mortality and incident cause-specific CVD hospitalisation since baseline, directly age-adjusted to 2006 New South Wales population. Male: ; female: .

Figure 2

HR (95% CI) for incident hospitalisation for cardiovascular disease (CVD) and all-cause mortality by number of natural teeth left. Events, number of events; rate, crude rate per 1000 person years; CVD, cardiovascular disease; IHD, ischaemic heart disease; PVD, peripheral vascular disease. HR¹, adjusted for age and sex; HR², additionally adjusted for tobacco smoking, alcohol consumption, Australian born status, region of residence, education, health insurance, physical activity and body mass index, with missing values in covariates were coded as a separate categories (0.3%, 1.7%, 0%, 0.03%, 1.3%, 0%, 4% and 7%, respectively). There were no missing values in age or sex. HR²s are plotted on a log scale and are represented with squares, with areas inversely proportional to the logarithm of events; 95% CIs are indicated by horizontal lines.

Figure 3

HR (95% CI) for incident hospitalisation for CVD and all-cause mortality by self-rated health of teeth and gums. Events, number of events; rate: crude rate per 1000 person years; CVD, cardiovascular disease; IHD, ischaemic heart disease; PVD, peripheral vascular disease. HR¹, adjusted for age and sex. HR², additionally adjusted for tobacco smoking, alcohol consumption, Australian born status, region of residence, education, private health insurance, physical activity and body mass index; missing values in covariates were coded as a separate category (0.3%, 1.7%, 0%, 0.03%, 1.3%, 0%, 4%, 7%, respectively). There were no missing values in age or sex. HR²s are plotted on a log scale and are represented with squares with areas inversely proportional to the logarithm of events; 95% CIs are indicated by horizontal lines.

Figure 4

HR for incident hospitalisation for IHD by number of natural teeth left (≥10 vs <10 teeth left), in a range of population subgroups. Events, number of events; IHD, ischaemic heart disease; BMI, body mass index; PA, physical activity. HR¹, adjusted for age and sex. HR², additionally adjusted for tobacco smoking, alcohol consumption, Australian born status, region of residence, education, private health insurance, physical activity and body mass index, where appropriate. HR², HRs are plotted on a log scale and are represented with squares with areas inversely proportional to the variance of logarithm of HR²s; 95% CIs are indicated by horizontal lines. The vertical dotted line represents the overall HR of incident hospitalisation for IHD.