Prediction of Factors Affecting Cognitive Performance in Pregnant Women using Robust Regression Methods

ion 1.45±0.83 1.88±0.40 0.003* Recall 2.64±1.68 2.90±1.46 0.448 Orientation 5.88±0.40 5.83±0.44 0.602 Cognitive Assessment Score 22.29±4.57 26.02±2.19 p<0.001* Independent samples t test; α:0.05;* Difference is statistically significant Doğaner A et al. Vol 7 No 1 (2021) Factors Affecting Cognitive Level in Pregnancy 64 Figure 1. Comparison of Sub-parameters of Cognitive Assessment Level The correlation between the cognitive assessment scores and the hormones in pregnant women are presented in Table 2. The relationship between the progesterone hormone levels and the scores obtained from the attention subdomain was found to be statistically significant (p = 0.030). It is observed that the attention scores declined with increased progesterone levels during pregnancy. Similarly, the relationship between the progesterone hormone and the abstraction subdomain scores was found to be statistically significant (p = 0.025). Increased progesterone hormone levels were associated with reduced abstraction ability in pregnant women. In general, the relationship between the cognitive assessment score and the progesterone hormone was found to be statistically significant (p = 0.025). High progesterone hormone levels in the pregnant women were associated with low levels of cognition. The effect of progesterone, age and TSH on cognitive assessment level is indicated in Figure 2. Table 2. Correlation of Hormones and Cognitive Functions in Pregnant Women Progesterone TSH Ferritin r p r p r p Visuospatial/Executive -0.072 0.662 -0.070 0.662 0.055 0.736 Naming -0.108 0.511 -0.079 0.619 0.307 0.054 Attention -0.349 0.030* -0.049 0.759 0.048 0.768 Language -0.172 0.296 0.054 0.735 0.113 0.486 Abstraction -0.358 0.025* -0.085 0.592 0.020 0.903 Recall -0.022 0.894 0.036 0.819 -0.003 0.984 Orientation -0.241 0.139 0.085 0.592 0.051 0.757 Cognitive Assessment Score -0.357 0.025* -0.040 0.801 -0.050 0.761 Pearson Correlation test; α:0,05;* Correlation is statistically significant Doğaner A et al. Vol 7 No 1 (2021) Factors Affecting Cognitive Level in Pregnancy 65 Figure 2. The effect of progesterone, age and TSH on cognitive assessment level The effects of age; the levels of TSH, ferritin, and progesterone, and the gestational week on cognition were examined. The findings are presented in Table 3. Age; the levels of progesterone, TSH, ferritin, and the gestational week explained 52% of the change in cognition. Of these factors; the age of the pregnant woman, the levels of progesterone and TSH had a statistically significant effect on cognition (p = 0.033; p = 0.04; p = 0.001, respectively). Changes in the age and levels of progesterone and TSH will potentially act on the scores of cognitive assessment in pregnant women. Increased age and high progesterone and TSH levels cause a decline in cognitive assessment score. No significant effects of ferritin and TSH levels and the gestational week were observed to affect cognitive assessment score. Table 3. Effect of Obstetric Characteristics on Cognitive Performance in Pregnant Women B t p Age -0.290 -0.17 0.033* Progesterone -0.039 -2.23 0.040* Tsh -0.901 -4.04 0.001* Ferritin -0.029 -1.98 0.057 Pregnancy Week -0.073 -1.57 0.127 Robust Regression Analysis; Andrew M estimator; α:0.05; R:0.52 *Effect is statistically significant Dependent Variables: Cognitive Assessment Score; Predictors: Age,Progesterone, Tsh, Ferritin, Pregnancy Week Discussion Pregnancy is a physiologically critical stage of transformation for women. Besides the physical changes and the alterations in the endocrine system and hormone levels; several problems in mental and cognitive functions may arise in pregnancy. In our study, factors causing cognitive impairment in pregnancy were investigated besides comparing the cognitive levels between the pregnant and nonpregnant women. The results demonstrated that visual execution, attention, and cognitive scores were lower in pregnant women compared to their nonpregnant counterparts. A study by De Groot et al. (2006) evaluated memory performance in pregnant women and in women in the control group (30). The authors reported that the memory performance was lower in pregnant women compared to the control group. In our study, recall function was found to be low in pregnant women. A study by Crawley, Grant, and Hinshaw (2008) compared the Doğaner A et al. Vol 7 No 1 (2021) Factors Affecting Cognitive Level in Pregnancy 66 severity of the cognitive decline in pregnancy compared to the control group (31). The comparison revealed that the cognitive scores of pregnant women were lower compared to those of women in the control group. The study by Aleshina et al. (2015) compared the cognitive scores between the groups of pregnant women suffering from autonomic nervous system disorders and the women in the control group (32). The authors observed significantly lower cognitive scores in pregnant women compared to the control group. Keskin et al. (2015) compared the cognitive functions between a group of pregnant women with gestational diabetes and a group of healthy pregnant women. Cognitive scores obtained from the assessment tests were significantly lower in pregnant women with gestational diabetes compared to the control group (33). The cognitive test scores of healthy pregnant women were reported to be 23.7 ± 3.7. It was observed that this value was close to the cognitive assessment scores (22.29 ± 4.57) of the pregnant women in our study. Several factors cause cognitive dysfunction during pregnancy. Of them, hormonal alterations are the leading factors. It was observed in the study that the hormones progesterone and TSH were significantly associated with the cognitive test scores. It was found out that as the progesterone and TSH levels increased, the cognitive test scores decreased. Gujski et al. (2017) carried out a study on thyroid hormones to determine cognitive impairment in postpartum women (34). That study demonstrated the effects of thyroid hormones on cognitive functions. In our study, the effect of TSH on cognitive functions in pregnant women was found out to be significant. High TSH levels are associated with low scores in cognitive tests. The number of studies conducted to determine the factors acting on the cognitive functions in pregnant women is quite a few in the literature. In our study, it was determined that not only progesterone and TSH hormones but also the age was effective on the cognitive functions during pregnancy. It was observed that increasing age in pregnant women was associated with cognitive impairment. Since cognitive impairment is usually observed in older people, several studies supporting this finding are available (35-37). High levels of progesterone and TSH have been observed as the major hormones affecting cognitive functions in pregnancy. Conclusion Pregnancy is an important process in a woman's life. It has been observed that the cognitive alterations occurring in pregnancy are not permanent and they are associated with physiological changes and the age of the pregnant woman. The findings of our study provide important information to the literature due to the limited number of studies in this field. The study results are important as they will provide preventive measures to be taken for ensuring that pregnant women can spend this period in the most comfortable way as much as possible. Furthermore, it is important to identify the responsible factors causing cognitive changes and know that these change in cognitive functions in pregnant women will be transient. Our study results demonstrate that pregnant women do not only undergo physical changes, but they experience alterations in their mental and cognitive functions as well. Moreover, the results indicate that pregnant women should be supported throughout this period. Doğaner A et al. Vol 7 No 1 (2021) Factors Affecting Cognitive Level in Pregnancy 67 Acknowledgement For this study, approval was obtained from the Clinical Research Ethics Committee of Kahramanmaras Sutcu Imam University with the registration number of 95 and the decision number of 2018/05-21. Conflict of Interest The authors declare that they have no conflict of interest. Funding This study was not funded.