Hormone replacement therapy and cognition in an Australian representative sample aged 60–64 years

Postmenopausal hormone therapy and cognition: effects of timing and treatment type

SETTING

Hormone therapy used for the management of postmenopausal symptoms in older women appears to result in variable effects on cognitive function, depending on study design, subjects, tests used, and types of therapy.

OBJECTIVE

To determine the effects of estrogen-only and estrogen plus progestogen preparations on cognitive performance (cognitive status, general and working memory) when taken 'early' and 'late' from the onset of menopause.

METHOD

The study consisted of 410 women who were participants in a longitudinal study, first recruited at age 40-80 years. They were tested for change over 5 years as an observational cohort by the Mini-Mental State Examination, National Adult Reading Test and the Wechsler Memory Scale Version 3. Cognitive decline, measured by age-adjusted scores, was defined as >or=10% negative change in each individual woman.

RESULTS

Controlling for age and lifestyle factors, and using the criterion of decrease in score >or=10% over 5 years for 'cognitive decline', 'early start' of hormone therapy (<3 years from menopause) was strongly associated with reduction in risk by the Mini-Mental State Examination (estrogen-only preparation, p = 0.005) but with increase in risk for general memory (with estrogen plus progestogen preparation, p = 0.02). Overall, there were no major effects on subgroups with type/timing of hormone therapy in relation to testing for a negative change in cognitive function.

CONCLUSION

'Early start' of estrogen-only hormone therapy was associated with reduced risk of global cognitive decline, and 'early start' estrogen-only and estrogen/progestogen hormone therapies showed increased risks of general memory decline. Even though this study did not have the power to discriminate between minor and mixed effects, it suggests that cognitive effects of hormone therapies may be mixed, depending on cognitive domain and timing of use/type of preparation.

Effects of different postmenopausal hormone therapy regimens on cerebral blood flow and cognitive functions

INTRODUCTION

The purpose of this study was to compare the effects of different postmenopausal hormone therapy regimens, namely conjugated equine estrogens (CEE), CEE plus medroxyprogesterone acetate (MPA), tibolone, and raloxifene on cerebral blood flow and cognitive functions.

METHODS

A total of 64 healthy postmenopausal women admitted to the Department of Obstetrics and Gynecology, Cumhuriyet University, Turkey were included in this study. Patients were divided into five groups with respect to the treatment protocols: CEE 0.625 mg/day (n=13); CEE 0.625 mg/day + MPA 2.5 mg/day (n=14); tibolone 2.5 mg/day (n=11); raloxifene 60 mg/day (n=9); and control (n=17). The CEE group included only women with surgical menopause. Those who were on hormonal therapy, who had previously used hormonal therapy, who had neurological disorders, or who did not accept the longterm follow-up were excluded from the study. Demographic and clinic characteristics were recorded. Before starting the therapy regimens, cerebral blood flow was evaluated by internal carotid artery and middle cerebral artery peak systolic velocity, and pulsatility index measurements via Doppler ultrasonography. Cognitive functions were evaluated by the Standardized Mini-Mental Test. The mean follow-up period was 10.9+/-2.4 months, ranging between 8 and 16 months. After the follow-up period, the cerebral blood flow, and cognitive function of each woman was re-evaluated.

RESULTS

Demographic and clinical characteristics of the women were not significantly different between the study groups (P>0.05). There were no significant differences between the pretreatment and posttreatment values for cerebral blood flow indices and cognitive function scores in any of the study groups (P>0.05).

CONCLUSION

Different postmenopausal hormone therapy regimens have not revealed any significant effects on either cerebral blood flow or cognitive function.

Is cognitive functioning detrimentally affected after early, induced menopause?

OBJECTIVE

Investigations into the cognitive effects of surgically and chemically induced menopause are frequently combined with naturally occurring menopause and hormone therapy. However, there is some evidence that women who undergo surgical menopause may experience more cognitive decline post surgery as well as more benefit from subsequent hormone therapy use than women who experience naturally occurring menopause. Little is known about the effects of chemically induced menopause on cognitive function. The aim of this review was to examine whether premature menopause affects cognitive functioning.

DESIGN

PubMed, MEDLINE, and PsychINFO searches of the literature published from 1988 to 2007 pertaining to the understanding of the relationships between induced menopause and cognitive dysfunction were reviewed. Those combining induced menopause with natural menopause, those involving a disease process (eg, dementia), and animal studies were excluded.

RESULTS AND CONCLUSIONS

Although smaller prospective studies have found that surgical menopause is associated with specific deficits in the memory (visual and verbal) and verbal fluency domains, larger randomized, controlled trials have generally found no effect of surgical menopause on cognitive functioning. The effects of chemical menopause are harder to assess as only three prospective trials have explicitly investigated the effect of induced menopause in the context of breast cancer treatment, and the results remain inconclusive. However, as surgical and chemical menopause both comprise the abrupt withdrawal of estrogen, there is the potential that this process may exert neurobiological effects that are different from those occurring with natural menopause and further prospective investigations comprising pre- and postsurgical/chemotherapy neuropsychological assessments are warranted.