Parity and risk of later-life maternal cardiovascular disease

Risk of coronary artery disease in women with history of pregnancies complicated by preeclampsia and LBW

Women with a history of pregnancy complicated by preeclampsia or intrauterine growth restriction and low infant birth weight looks at a higher risk for subsequent ischemic heart disease.

OBJECTIVE

To determine the relationship between pregnancy complications and maternal coronary artery disease (CAD) in the future.

MATERIALS AND METHOD

We performed a case-control study on 690 patients (345 patients in each group) referred to Tehran Heart Center. Women with CAD were in the case group and women without CAD were in the control group. The history of pregnancy complications (including preeclampsia, low birth weight [LBW] delivery, preterm labor and gestational hypertension) was evaluated in the two groups.

RESULTS

12.5% of the patients in the case group had a history of preeclampsia, compared with the control group (1.7%). (p < 0. 0001). Seven percent of the patients in the case group and 0.9% of the patients in the control group had history of LBW delivery. The difference was significant (p < 0.0001). A history of preterm labor was recorded in 11% of cases and 3.2% of controls. Performing multivariate analysis showed that there is a strong association between preeclampsia and CAD (OR: 16.92; 95% CI; p < 0.0001), LBW delivery and CAD (OR: 6.52; 95% CI; p: 0.0038), and also between high parity and CAD. (OR: 1.135; 95% CI; p: 0.0479).

CONCLUSION

Our results suggest preeclampsia, LBW delivery and high parity of the mother as independent risk factors for CAD in the future.

Reproductive history and mortality from cardiovascular disease among women textile workers in Shanghai, China

BACKGROUND

Few studies have examined the possible effects of reproductive factors on cardiovascular disease (CVD) risks in Asian women.

METHODS

A cohort of 267,400 female textile workers in Shanghai, China, was administered a questionnaire at enrolment (1989-91) and followed for mortality through 2000. Relative risks (hazard ratios) for ischaemic heart disease (IHD), ischaemic stroke and haemorrhagic stroke were calculated using Cox proportional hazards modelling, adjusting for relevant co-variates.

RESULTS

Risks were not consistently associated with age at menopause, parity, stillbirths, miscarriages or duration of lactation. An increasing trend in IHD mortality risk, but not stroke, was observed with decreasing age at menarche. There was no evidence of increased CVD mortality risk by oral or injectable contraceptive use or induced abortions. As expected, greater mortality rates from CVD and increased CVD risks were also observed with smoking.

CONCLUSIONS

Use of steroid contraceptives, induced abortions and reduced parity from China's one-child-per-family policy has not had an adverse effect on risk of CVD mortality in this cohort.

The associations between nationality, fertility history and diabetes-related mortality: a retrospective cohort study in the Brussels-Capital Region (2001-2005)

BACKGROUND

The relationship between women's parity and diabetes mortality has been investigated in several studies, with mixed results. This study aims to establish if parity and age at first birth are associated with diabetes-related mortality and if these factors contribute to variations in diabetes-related mortality among women with different nationalities.

METHODS

Data of the 2001 census are linked to registration records of all deaths and emigrations (period 2001-2005). The study population comprises all female inhabitants of the Brussels-Capital Region aged 45-74 of either Belgian or North African nationality (n = 108 296). Age-standardized mortality rates (direct standardization) and mortality rate ratios (Poisson's regression) are computed.

RESULTS

Both parity and age at first birth are associated with diabetes-related mortality. Highest risks of dying from diabetes are observed among grandmultiparous women and teenage mothers. Differences in diabetes-related mortality according to nationality are observed. Age-standardized diabetes mortality rates are higher in North African [ASMR = 417.4/100,000; 95% confidence interval (CI) 227.2-607.7] than in Belgian women (ASMR = 184.0/100,000; 95% CI 157.3-210.8). Taking parity, age at first birth and education into account, these differences largely disappear.

CONCLUSIONS

Reproductive factors are associated with diabetes-related mortality and play an important part in the higher diabetes-related mortality of North African compared with Belgian women.

External review and validation of the Swedish national inpatient register

Background

The Swedish National Inpatient Register (IPR), also called the Hospital Discharge Register, is a principal source of data for numerous research projects. The IPR is part of the National Patient Register. The Swedish IPR was launched in 1964 (psychiatric diagnoses from 1973) but complete coverage did not begin until 1987. Currently, more than 99% of all somatic (including surgery) and psychiatric hospital discharges are registered in the IPR. A previous validation of the IPR by the National Board of Health and Welfare showed that 85-95% of all diagnoses in the IPR are valid. The current paper describes the history, structure, coverage and quality of the Swedish IPR.

Methods and results

In January 2010, we searched the medical databases, Medline and HighWire, using the search algorithm "validat* (inpatient or hospital discharge) Sweden". We also contacted 218 members of the Swedish Society of Epidemiology and an additional 201 medical researchers to identify papers that had validated the IPR. In total, 132 papers were reviewed. The positive predictive value (PPV) was found to differ between diagnoses in the IPR, but is generally 85-95%.

Conclusions

In conclusion, the validity of the Swedish IPR is high for many but not all diagnoses. The long follow-up makes the register particularly suitable for large-scale population-based research, but for certain research areas the use of other health registers, such as the Swedish Cancer Register, may be more suitable.