Midlife blood pressure predicts future diastolic dysfunction independently of blood pressure

Impact of Blood Pressure in the Early 40s on Left Atrial Volumes in the Mid-60s: Data From the ACE 1950 Study

Background

Echocardiographic measures of left atrial volumes are powerful predictors of cardiovascular events and important for assessing diastolic dysfunction. Despite this, there is limited knowledge of factors influencing left atrial remodeling. In particular, the impact of blood pressure in those in their early 40s on left atrial volumes later in life has not been sufficiently elucidated.

Methods and Results

We linked data from individuals born in 1950 who participated in the Age 40 Program, and the ACE (Akershus Cardiac Examination) 1950 Study. We divided the study population into quartiles of systolic blood pressure in their early 40s and assessed the proportion of individuals with an enlarged left atrium in their mid‐60s. The associations between blood pressure and left atrial volumes were assessed in linear regression analyses. Of the 2591 individuals included in this study, 1302 (50.3%) were women, and the mean age in the Age 40 Program was 40.1±0.3 years. Systolic blood pressure was 128.1±13.6 mm Hg and diastolic blood pressure was 78.3±9.5 mm Hg. Mean age in the ACE 1950 Study was 64.0±0.6 years. The proportion of individuals with an enlarged left atrium increased across the quartiles of systolic blood pressure (P=0.001). Systolic blood pressure was independently associated with left atrial volumes; the end‐systolic volume was 0.09 mL (95% CI, 0.04–0.14 mL) larger per 1‐mm Hg higher systolic blood pressure.

Conclusions

Our findings suggest that increased blood pressure in those in their early 40s is relevant for left atrial remodeling later in life.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT01555411.

Association of Midlife Cardiovascular Risk Factors With the Risk of Heart Failure Subtypes Later in Life

BACKGROUND

Independent associations between cardiovascular risk factor exposures during midlife and later life development of heart failure (HF) with preserved ejection fraction (HFpEF) versus reduced EF (HFrEF) have not been previously studied.

METHODS

We pooled data from 4 US cohort studies (Atherosclerosis Risk in Communities, Cardiovascular Health, Health , Aging and Body Composition, and Multi-Ethnic Study of Atherosclerosis) and imputed annual risk factor trajectories for body mass index, systolic and diastolic blood pressure, low-density lipoprotein and high-density lipoprotein cholesterol, and glucose starting from age 40 years. Time-weighted average exposures to each risk factor during midlife and later life were calculated and analyzed for associations with the development of HFpEF or HFrEF.

RESULTS

A total of 23,861 participants were included (mean age at first in-person visit, 61.8 ±1 0.2 years; 56.6% female). During a median follow-up of 12 years, there were 3666 incident HF events, of which 51% had EF measured, including 934 with HFpEF and 739 with HFrEF. A high midlife systolic blood pressure and low midlife high-density lipoprotein cholesterol were associated with HFrEF, and a high midlife body mass index, systolic blood pressure, pulse pressure, and glucose were associated with HFpEF. After adjusting for later life exposures, only midlife pulse pressure remained independently associated with HFpEF.

CONCLUSIONS

Midlife exposure to cardiovascular risk factors are differentially associated with HFrEF and HFpEF later in life. Having a higher pulse pressure during midlife is associated with a greater risk for HFpEF but not HFrEF, independent of later life exposures.

Association between antecedent blood pressure, hypertension-mediated organ damage and cardiovascular outcome

Purpose: The objective of this study was to test if combining antecedent systolic blood pressure (SBP) with traditional risk factors and hypertension-mediated organ damage (HMOD) improves risk stratification for subsequent cardiovascular disease.Materials and methods: 1910 subjects participated in this study. Antecedent SBP was defined as the average of measurements obtained in 1982 and in 1987. Current SBP was obtained in 1993. HMOD were examined in 1993. HMOD was defined as either atherosclerotic plaque(s), increased pulse wave velocity, increased urine albumin creatinine ratio (above the 90th percentile) or left ventricular hypertrophy. Major adverse cardiovascular events (MACE) including myocardial infarction, cerebrovascular disease, heart failure and arrhythmia were obtained from national registries.Results: Subjects were divided into two age categories: a middle-aged group (aged 41 or 51) and an older group (aged 61 or 71). From 1993 to 2010, 425 events were observed. In multivariable analysis with both current and antecedent SBP adjusted for traditional risk factors, current SBP was associated with each measure of HMOD whilst antecedent SBP was not significantly associated with urine albumin creatinine ratio in the older group, LVMI in the middle-aged group, or the presence of plaque in any of the age groups (all p > 0.15). When current and antecedent SBP were evaluated together, current SBP was not associated with MACE in the middle-aged subgroup [HR = 1.09 (0.96-1.22), p = 0.18] but remained associated with MACE in the older subgroup [HR = 1.21 (1.10-1.34), p < 0.01]. Contrariwise, antecedent SBP was only associated with MACE in the middle-aged subgroup [HR = 1.24 (1.04-1.48), p = 0.02]. Adding antecedent SBP to traditional risk factors did not improve the predictive accuracy of the survival model.Conclusion: In healthy non-medicated middle-aged subjects, antecedent SBP is associated with cardiovascular outcome independently of current BP, traditional risk factors and HMOD. However, improvement in risk stratification seems to be limited.

The relationship between pubertal timing and markers of vascular and cardiac structure and function in men and women aged 60-64 years

Earlier age at menarche has been associated with higher risk of coronary heart disease, but the mechanisms underlying the association remain unclear. We assessed the relationship of pubertal timing, in both men (n = 672) and women (n = 713), with vascular (carotid intima-media thickness (cIMT), pulse wave velocity (PWV)) and cardiac (left ventricular (LV) structure and function) measures recorded at age 60–64 yrs in a British birth cohort study. Regression models found that earlier menarche was associated with higher (more adverse) LV mass, LV end diastolic volume and left atrial volume, but not with other cardiac measures, cIMT or PWV. Associations were attenuated after adjustment for either adult or childhood BMI (e.g. mean difference in LV mass per year later menarche: −4.2 g (95% CI:−7.0,−1.4) reducing to −2.2 g (95% CI:−4.7,0.4) after adjustment for adult BMI). There were no associations among men, despite those fully mature at 15 yrs having higher blood pressure than the least mature group by 10.21 mmHg (95% CI:19.45,0.98). Any effect of pubertal timing on vascular and cardiac structure and function is likely to be small and primarily confounded by pre-pubertal BMI and/or mediated through adult adiposity.

Vascular risk factors for male and female urgency urinary incontinence at age 68 years from a British birth cohort study

Objective

To investigate the prevalence of urgency urinary incontinence (UUI) at age 68 years and the contribution of vascular risk factors to male and female UUI pathogenesis in addition to the associations with raised body mass index (BMI).

Subjects and methods

In all, 1 762 participants from the Medical Research Council (MRC) National Survey for Health and Development birth cohort who answered the International Consultation on Incontinence Questionnaire short form (ICIQ‐SF), at age 68 years, were included. Logistic regression was used to estimate associations between UUI and earlier life vascular risk factors including: lipid status, diabetes, hypertension, BMI, previous stroke or transient ischaemic attack (TIA) diagnosis; adjusting for smoking status, physical activity, co‐presentation of stress UI symptoms, educational attainment; and in women only, type of menopause, age at period cessation, and use of hormone replacement therapy (HRT).

Results

UUI was reported by 12% of men and 19% of women at age 68 years. Female sex, previous stroke or TIA diagnosis, increased BMI and hypertension (in men only) at age 60–64 years were independent risk factors for UUI. Female sex, increased BMI, and a previous diagnosis of stroke/TIA increased the relative risk of more severe UUI symptoms. Type and timing of menopause and HRT use did not alter the estimated associations between UUI and vascular risk factors in women.

Conclusion

Multifactorial mechanisms lead to UUI and vascular risk factors may contribute to the pathogenesis of bladder overactivity in addition to higher BMI. Severe UUI appears to be a distinct presentation with more specific contributory mechanisms than milder UUI.

Adjustment for time-invariant and time-varying confounders in 'unexplained residuals' models for longitudinal data within a causal framework and associated challenges

‘Unexplained residuals’ models have been used within lifecourse epidemiology to model an exposure measured longitudinally at several time points in relation to a distal outcome. It has been claimed that these models have several advantages, including: the ability to estimate multiple total causal effects in a single model, and additional insight into the effect on the outcome of greater-than-expected increases in the exposure compared to traditional regression methods. We evaluate these properties and prove mathematically how adjustment for confounding variables must be made within this modelling framework. Importantly, we explicitly place unexplained residual models in a causal framework using directed acyclic graphs. This allows for theoretical justification of appropriate confounder adjustment and provides a framework for extending our results to more complex scenarios than those examined in this paper. We also discuss several interpretational issues relating to unexplained residual models within a causal framework. We argue that unexplained residual models offer no additional insights compared to traditional regression methods, and, in fact, are more challenging to implement; moreover, they artificially reduce estimated standard errors. Consequently, we conclude that unexplained residual models, if used, must be implemented with great care.

Conventional and Ambulatory Blood Pressure as Predictors of Diastolic Left Ventricular Function in a Flemish Population

Background

No longitudinal study compared associations of echocardiographic indexes of diastolic left ventricular function studies with conventional (CBP) and daytime ambulatory (ABP) blood pressure in the general population.

Methods and Results

In 780 Flemish (mean age, 50.2 years; 51.7% women), we measured left atrial volume index (LAVI), peak velocities of the transmitral blood flow (E) and mitral annular movement (e′) in early diastole and E/e′ 9.6 years (median) after CBP and ABP. In adjusted models including CBP and ABP, we expressed associations per 10/5‐mm Hg systolic/diastolic blood pressure increments. LAVI and E/e′ were 0.65/0.40 mL/m² and 0.17/0.09 greater with higher systolic/diastolic ABP (P≤0.028), but not with higher baseline CBP (P≥0.086). e′ was lower (P≤0.032) with higher diastolic CBP (−0.09 cm/s) and ABP (−0.19 cm/s). When we substituted baseline CBP by CBP recorded concurrently with echocardiography, LAVI and E/e′ remained 0.45/0.38 mL/m² and 0.15/0.08 greater with baseline ABP (P≤0.036), while LAVI (+0.53 mL/m²) and E/e′ (+0.19) were also greater (P<0.001) in relation to concurrent systolic CBP. In categorized analyses of baseline data, sustained hypertension or masked hypertension compared with normotension or white‐coat hypertension was associated with greater LAVI (24.0 versus 22.6 mL/m²) and E/e′ (7.35 versus 6.91) and lower e′ (10.7 versus 11.6 cm/s; P≤0.006 for all) with no differences (P≥0.092) between normotension and white‐coat hypertension or between masked hypertension and sustained hypertension.

Conclusions

ABP is a long‐term predictor of diastolic left ventricular function, statistically outperforming distant but not concurrent CBP. Masked hypertension and sustained hypertension carry equal risk for deterioration of diastolic left ventricular function.

Birthweight, childhood growth and left ventricular structure at age 60-64 years in a British birth cohort study

BACKGROUND

High left ventricular mass (LVM) is an independent predictor of cardiovascular disease and mortality, but information relating LVM in older age to growth in early life is limited. We assessed the relationship of birthweight, height and body mass index (BMI) and overweight across childhood and adolescence with later life left ventricular (LV) structure.

METHODS

We used data from the MRC National Survey of Health and Development (NSHD) on men and women born in 1946 in Britain and followed up ever since. We use regression models to relate prospective measures of birthweight and height and BMI from ages 2-20 years to LV structure at 60-64 years.

RESULTS

Positive associations of birthweight with LVM and LV end diastolic volume (LVEDV) at 60-64 years were largely explained by adult height. Higher BMI, greater changes in BMI and greater accumulation of overweight across childhood and adolescence were associated with higher LVM and LVEDV and odds of concentric hypertrophy. Those who were overweight at two ages in early life had a mean LVM 11.5 g (95% confidence interval: -2.19,24.87) greater, and a mean LVEDV 10.0 ml (3.7,16.2) greater, than those who were not overweight. Associations were at least partially mediated through adult body mass index. Body size was less consistently associated with relative wall thickness (RWT), with the strongest association being observed with pubertal BMI change [0.007 (0.001,0.013) per standard deviation change in BMI 7-15 years]. The relationships between taller childhood height and LVM and LVEDV were explained by adult height.

CONCLUSIONS

Given the increasing levels of overweight in contemporary cohorts of children, these findings further emphasize the need for effective interventions to prevent childhood overweight.