Pulmonary function and adverse cardiovascular outcomes: Can cardiac function explain the link?

Lipoprotein(a) and Lung Function Are Associated in Older Adults: Longitudinal and Cross-Sectional Analyses

While numerous studies have confirmed a causal association between lipoprotein(a) [Lp(a)] and cardiovascular diseases, only a few studies have assessed the relationship between Lp(a) and pulmonary health, with inconsistent findings regarding this topic. This study's aim was to examine whether levels of serum Lp(a) are associated with lung function in a dataset of relatively healthy older adults. We used longitudinal data collected at two time points 7.4 ± 1.5 years apart from 679 participants (52% women, 68 [65-71] years old) from the Berlin Aging Study II (BASE-II). Multiple linear regression models adjusting for covariates were applied to examine the association between Lp(a) and lung function. The forced expiratory volume in one second (FEV1) and the forced vital capacity (FVC) were higher in both men and women with higher Lp(a) levels. However, since this association between lung function parameters and Lp(a) was not supported by Mendelian randomization analyses using recent genome-wide association study data, these relationships should be investigated in future work, as the observed differences are, in part, considerable and potentially clinically relevant.

Association between spirometry pattern, left ventricular diastolic function, and mortality

BACKGROUND

Spirometric abnormalities have been related to incident heart failure in general population, who generally have preserved left ventricular ejection fraction (LVEF). We aimed to investigate the association between spirometric indices, cardiac functions and clinical outcomes.

METHODS

Subjects presenting with exertional dyspnoea and received spirometry and echocardiography were eligible for this study. Forced vital capacity (FVC) and forced expiratory volume in the first second (FEV1)/FVC ratio were measured to define the spirometry patterns: normal (FEV1/FVC ≥ 70%, FVC ≥ 80%), obstructive (FEV1/FVC < 70%, FVC ≥ 80%), restrictive pattern (FEV1/FVC ≥ 70%, FVC < 80%) and mixed (FEV1/FVC < 70%, FVC < 80%). The diastolic dysfunction index (DDi) was the counts of the indicators, including septal e' velocity <7 cm/s, septal E/e' > 15, pulmonary artery systolic pressure > 35 mmHg and left atrial dimension >40 mm.

RESULTS

Among a total of 8669 participants (65.8 ± 16.3 years, 56% men), 3739 (43.1%), 829 (9.6%), 3050 (35.2%) and 1051 (12.1%) had normal, obstructive, restrictive and mixed spirometry pattern, respectively. Subjects with restrictive or mixed spirometry pattern had higher DDi and worse long-term survival than those with obstructive or normal ventilation. FVC but not FEV1/FVC was predictive of 5-year mortality, independent of age, sex, renal function, LVEF, DDi, body mass index, and comorbidities (hazard ratio, 95% confidence intervals: .981, .977-.985). Furthermore, there was an inverse nonlinear relationship between FVC and DDi, suggesting the declined FVC may mediate 43% of the prognostic hazard of left ventricular diastolic dysfunction.

CONCLUSIONS

The restrictive spirometry pattern or the declined FVC was associated with left ventricular diastolic dysfunction, which aggravated the long-term mortality in the ambulatory dyspnoeic subjects.

Low lung function, sudden cardiac death and non-fatal coronary events in the general population

BACKGROUND

Many of those who suffer from a first acute coronary event (CE) die suddenly during the day of the event, most of them die outside hospital. Poor lung function is a strong predictor of future cardiac events; however, it is unknown whether the pattern of lung function impairment differs for the prediction of sudden cardiac death (SCD) versus non-fatal CEs. We examined measures of lung function in relation to future SCD and non-fatal CE in a population-based study.

METHODS

Baseline spirometry was assessed in 28 584 middle-aged subjects, without previous history of CE, from the Malmö Preventive Project. The cohort was followed prospectively for incidence of SCD (death on the day of a first CE, inside or outside hospital) or non-fatal CE (survived the first day). A modified version of the Lunn McNeil's competing risk method for Cox regression was used to run models for both SCD and non-fatal CE simultaneously.

RESULTS

A 1-SD reduction in forced expiratory volume in 1 s (FEV₁) was more strongly associated with SCD than non-fatal CE even after full adjustment (FEV₁: HR for SCD: 1.23 (1.15 to 1.31), HR for non-fatal CE 1.08 (1.04 to 1.13), p value for equal associations=0.002). Similar associations were found for forced vital capacity (FVC) but not FEV₁/FVC. The results remained significant even in life-long never smokers (FEV₁: HR for SCD: 1.34 (1.15 to 1.55), HR for non-fatal CE: 1.11 (1.02 to 1.21), p value for equal associations=0.038). Similar associations were seen when % predicted values of lung function measures were used.

CONCLUSIONS

Low FEV₁ is associated with both SCD and non-fatal CE, but consistently more strongly associated with future SCD. Measurement with spirometry in early life could aid in the risk stratification of future SCD. The results support the use of spirometry for a global assessment of cardiovascular risk.

Rethinking Chronic Obstructive Pulmonary Disease. Chronic Pulmonary Insufficiency and Combined Cardiopulmonary Insufficiency

Almost 70 years ago, Drs. Baldwin, Cournand, and Richards defined chronic pulmonary insufficiency by the presence of respiratory symptoms, radiologic evidence of pulmonary emphysema on chest radiography, and physiologic gas trapping. A decade later, airflow obstruction on spirometry was added to the definition and insufficiency became a disease. Contemporary studies are reviving the diagnostic approach described by these early luminaries, with researchers finding that symptomatic smokers with preserved spirometry have increased exacerbations and that smokers and non-smokers with normal spirometry but emphysema on chest computed tomography have increased mortality. Hence, the Baldwin-Cournand-Richards concept of disease defined by respiratory symptoms, radiologic findings, and physiology-regardless of spirometric criteria-is being rediscovered. Baldwin, Cournand, and Richards also stated that "functionally, it is obvious that the pulmonary and circulatory apparatus are one unit," and they defined combined cardiopulmonary insufficiency as chronic pulmonary insufficiency with (left or right) cardiac and pulmonary artery enlargement. They appreciated the complexity of these interactions, which include the potential role of gas trapping in heart failure with reduced ejection fraction; the impact of emphysema on blood flow in heart failure with preserved ejection fraction; multiple contributions to cor pulmonale with increased pulmonary artery pressure; and cor pulmonale parvus in emphysema; all of which may be amenable to specific therapeutic interventions. Given the complexity of heart-lung interactions originally identified by Baldwin, Cournand, and Richards and the potentially large therapeutic opportunities, large-scale studies are still warranted to find specific therapies for subphenotypes of combined cardiopulmonary insufficiency.

Association of lung function with cardiovascular risk: a cohort study

BACKGROUND

The potential effects of pulmonary dysfunction on cardiovascular diseases (CVD) are receiving attention. We aimed to investigate and quantify the cross-sectional and longitudinal associations between lung function and overall cardiovascular risk among Chinese general population.

METHODS

We studied 4019 participants from the Wuhan-Zhuhai cohort, with a follow-up of 3 years. A multivariable risk algorithm generated from the Framingham study was used to calculate individuals' overall cardiovascular risk i.e. 10-Year CVD Risk, which was further classified into 2 categories: low (< 10%) and high (≥10%) CVD risk. General linear model and logistic regression model were separately used to assess the associations of lung function with continuous and dichotomous 10-Year CVD Risk.

RESULTS

Cross-sectionally, each 5% decrease in FEV₁/FVC was associated with a 0.47% increase in 10-Year CVD Risk (P < 0.001). The adjusted odds ratio (OR) (95% confidence interval [CI]) for the prevalence of high CVD risk (10-Year CVD Risk≥10%) was 1.12 (1.07, 1.17) corresponding to each 5% decrease in FEV₁/FVC. The OR (95% CI) for high CVD risk in the lowest group of FEV₁/FVC (< 70% i.e. chronic obstructive pulmonary disease [COPD]) was 2.37 (1.43, 3.91) when compared with the highest group. Longitudinally, the adjusted risk ratio (RR) (95% CI) for the incidence of high CVD risk was 1.14 (1.03, 1.25) with each 5% decrease in baseline FEV₁/FVC. Compared with the highest group of FEV₁/FVC, the RR (95% CI) for high CVD risk in the lowest group (COPD) was 4.06 (1.46, 11.26). Analyses of 10-Year CVD Risk with FVC or FEV₁ showed similar trends and significant associations (all P < 0.05).

CONCLUSION

Reduced lung function was cross-sectionally and longitudinally associated with increased cardiovascular risk in Chinese general population.