Dietary Antioxidant Capacity and Its Association with Preeclampsia

The association between diet quality index-international and dietary diversity score with preeclampsia: a case-control study

BACKGROUND

Preeclampsia is a significant complication that occurs during the second half of pregnancy. Recent studies have indicated that dietary factors play a crucial role in the development of preeclampsia. The Diet Quality Index-International (DQI-I) and Dietary Diversity Score (DDS) are appropriate indices for assessing the quality of foods, meals, and diets. This study aimed to investigate the relationship between DQI-I, DDS, and preeclampsia.

METHODS

This study utilized a case-control design. A total of 90 newly diagnosed preeclampsia cases and 90 healthy controls were included from a referral hospital in Tabriz, Iran. DQI-I and DDS were calculated based on information obtained from a reliable Food Frequency Questionnaire consisting of 168 food items, which assessed participants' usual diet. Logistic regression analysis adjusted for age, body mass index, education, family history of preeclampsia, and total energy intake was used to estimate odds ratios (ORs).

RESULTS

The mean age and pre-pregnancy body mass index of the participants were: 27.14 ± 4.40 years and 26.09 ± 3.33 kg/m2, respectively. After adjusting for various confounders, we found significant inverse association between the risk of developing preeclampsia and both DQI-I and DDS. The highest quartile of DQI-I had a significantly lower risk of developing preeclampsia compared to the first quartile (OR = 0.02, 95% CI [0.005, 0.08]) (P < 0.001). Similarly, the highest quartile of DDS had a significantly lower risk of developing preeclampsia compared to the first quartile (OR = 0.09, 95% CI [0.03, 0.31]) (P = 0.001).

CONCLUSIONS

Our findings suggest that maintaining a high-quality and diverse diet is associated with a lower risk of preeclampsia. Further studies are needed to confirm these associations and explore potential causal relationships.

Associations of dietary patterns and pre-eclampsia: a matched case-control study

Little is known about the effects of dietary patterns on prevalent pre-eclampsia in Chinese population. This study aimed to investigate the associations between dietary patterns and the odds of pre-eclampsia among Chinese pregnant women. A 1:1 age- and gestational week-matched case-control study was conducted between March 2016 and February 2019. A total of 440 pairs of pre-eclampsia cases and healthy controls were included. Dietary intakes were assessed by a seventy-nine-item FFQ and subsequently grouped into twenty-eight distinct groups. Factor analysis using the principal component method was adopted to derive the dietary patterns. Conditional logistic regression was used to analyse the associations of dietary patterns with prevalent pre-eclampsia. We identified four distinct dietary patterns: high fruit-vegetable, high protein, high fat-grain and high salt-sugar. We found that high fruit-vegetable dietary pattern (quartile (Q)4 v. Q1, OR 0·71, 95 % CI 0·55, 0·92, Ptrend = 0·013) and high protein dietary pattern (Q4 v. Q1, OR 0·72, 95 % CI 0·54, 0·95, Ptrend = 0·011) were associated with a decreased odds of pre-eclampsia in Chinese pregnant women. Whereas high fat-grain dietary pattern showed a U-shaped association with pre-eclampsia, the lowest OR was observed in the third quartile (Q3 v. Q1, OR 0·75, 95 % CI 0·57, 0·98, Ptrend = 0·111). No significant association was observed for high salt-sugar dietary pattern. In conclusion, pregnancy dietary pattern characterised by high fruit-vegetable or high protein was found to be associated with a reduced odds of pre-eclampsia in Chinese pregnant women.

The Total Dietary Antioxidant Capacity, Its Seasonal Variability, and Dietary Sources in Cardiovascular Patients

The favourable role of dietary antioxidants in cardiovascular diseases (CVDs) and protection from them is widely discussed, and total dietary antioxidant capacity (TAOX) is perceived as a diet-quality marker. Data concerning TAOX and its dietary sources related to seasonal variability are limited. We aimed to analyse the TAOXs, seasonal variability, and sources in the daily diets of CVD patients. A total of 143 subjects (82 men, 61 women) since CVD problems were studied. Seasonal recalls were collected regarding dietary sources of antioxidant compounds in spring, summer, autumn, and winter. A food frequency questionnaire was used. The total dietary antioxidant capacity (in μmolTE/day) was calculated for each season. The primary sources of antioxidants in cardiovascular patients' diets were drinks (33%), fruits (28%), vegetables (16%), and black tea (14%). The TAOXs of CVD patients' diets significantly depended on the season (p < 0.001) and were highest in the summer and lowest in the spring. This seasonal variation in consumption was noted. Our findings suggest that a diet characterised with a TAOX might be subjected to fluctuations between seasons. We suggest considering modifications in the dietary recommendations for cardiovascular patients with a low antioxidant capacity between seasons.

Antioxidants in Pregnancy: Do We Really Need More Trials?

Human pregnancy can be affected by numerous pathologies, from those which are mild and reversible to others which are life-threatening. Among these, gestational diabetes mellitus and hypertensive disorders of pregnancy with subsequent consequences stand out. Health problems experienced by women during pregnancy and postpartum are associated with significant costs to health systems worldwide and contribute largely to maternal mortality and morbidity. Major risk factors for mothers include obesity, advanced maternal age, cardiovascular dysfunction, and endothelial damage; in these scenarios, oxidative stress plays a major role. Markers of oxidative stress can be measured in patients with preeclampsia, foetal growth restriction, and gestational diabetes mellitus, even before their clinical onset. In consequence, antioxidant supplements have been proposed as a possible therapy; however, results derived from large scale randomised clinical trials have been disappointing as no positive effects were demonstrated. This review focuses on the latest evidence on oxidative stress in pregnancy complications, their early diagnosis, and possible therapies to prevent or treat these pathologies.

Dietary total antioxidant capacity and risk of ulcerative colitis: A case-control study

OBJECTIVE

Data on the association between the antioxidant capacity of a diet and the risk of ulcerative colitis (UC) are scarce. This study aimed to assess whether a relationship exists between dietary total antioxidant capacity (TAC) and the odds of UC in Iranian adults.

METHODS

In this case-control study, patients with UC and age-matched healthy controls were recruited from a hospital clinic. All participants completed a validated 168-item food frequency questionnaire, the results of which were subsequently used to generate dietary TAC. Ferric reducing-antioxidant power values were used to calculate dietary TAC.

RESULTS

Altogether 62 patients with UC and 124 healthy controls were enrolled. UC patients had a higher calorific intake (P < 0.01), and consumed more monounsaturated fatty acids (P < 0.01), vitamin B₉ (P < 0.01) and calcium (P = 0.02) compared with healthy controls, while the control group had a higher vitamin C intake than the participants with UC (P < 0.01). In a fully adjusted model, participants who were in the highest quartile of dietary TAC had a lower risk of UC (odds ratio 0.11, 95% confidence interval 0.01-0.73).

CONCLUSIONS

A higher dietary TAC score was associated with lower odds of UC in this case-control study. Further elucidation of the role of key dietary elements is now warranted.

Circulating Interleukin-6 Level, Dietary Antioxidant Capacity, and Risk of Colorectal Cancer

Chronic inflammation is one of the causes of colorectal cancer (CRC), and circulating levels of inflammatory biomarkers have been linked to tumor promotion and progression. We aimed to evaluate the interleukin-6 (IL-6) level in CRC patients and determine whether a diet rich in antioxidants was associated with CRC. This study included 654 cases and 1312 controls matched for age and sex. We measured the plasma IL-6 concentration and estimated dietary antioxidant capacity based on oxygen radical absorbance capacity (ORAC) combined with a 106-item semiquantitative food frequency questionnaire. The IL-6 concentration was significantly increased in individuals with CRC (OR _{Q4 vs. Q1}, 95% CI = 6.23, 4.10-9.45, p < 0.001). High dietary ORAC showed an inverse association with CRC (total ORAC OR _{Q4 vs. Q1}, 95% CI = 0.26, 0.16-0.40, p < 0.001; total phenolics = 0.32, 0.21-0.50, p < 0.001). We found that low dietary ORAC was associated with a significant increase in CRC in the group with elevated IL-6 levels (total ORAC OR _{Q4 vs. Q1}, 95% CI = 4.34, 3.12-6.02, p < 0.001; total phenolics = 4.61, 3.33-6.39, p < 0.001). This study suggested an inverse association between dietary antioxidant capacity and IL-6 level among patients with CRC.