Strengths and limitations
This study included large numbers of women with severe disease which
enabled us to assess different phenotypes of pre-eclampsia. To perform
assessments in women with severe disease such as eclampsia is difficult
in high income countries as the incidence is low, around
50/110,000.25 Performing this study in our setting,
where eclampsia is more prevalent, enabled us to recruit this cohort in
a short time period. Validated tests which included both subjective and
objective cognitive function assessments were used. We also assessed
cognition before and after delivery using different methods. To our
knowledge, this study is the first to examine cognitive function in
close proximity to onset of pre-eclampsia.
Our study does have limitations. Women with pre-eclampsia with severe
features may have been more tired at the time of cognitive function
testing. We tried to correct for this by adjusting for “time from
delivery to discharge” in the analyses. In addition, no testing for
anxiety or depression was performed. Though, very few women reported
symptoms suggestive of depression during pregnancy and we adjusted for
gestational age as a proxy for maternal and neonatal complications that
could be related to anxiety and depression postpartum. The group of
women with pulmonary oedema was small, introducing the risk of a type 2
error in the analyses where the differences in MoCA test were attenuated
after adjustment for confounders. Lastly, there was no follow up after
discharge. Women who deliver at Tygerberg hospital often live in
informal settlements and it is challenging for them to return for follow
up visits due to social circumstances. Finally, women rated their
cognitive function prior to diagnosis or delivery retrospectively when
doing the CFQ assessment that could introduce bias. However, the CFQ is
the most common test used in the field and our results compare to
previously published studies.