Charactertizing Growth Hormone Deficiency in Traumatic Brain Injury

A 25-question, self-administered, condition specific quality of life measure used to determine the extent to which growth hormone deficiency has affected the patient's quality of life. Participants are instructed to answer "yes" or "no" to statements relating to problems with memory and concentration, tiredness, tenseness, social isolation and self-confidence. Higher scores indicate greater symptom burden and lower quality of life.

Provocative glucagon stimulation testing completed by endocrinology. Peak growth hormone of less than 3mcg/L indicative of growth hormone deficiency

Assesses for mild cognitive impairment. Total possible score ranges from 0 to 30, with higher scores indicative of better outcomes.

A 20-item self-reported questionnaire that measures central fatigue and altered cognition, , with 10 items comprising each subscale. Items are rated on an electronic visual analog scale (0-100), with higher scores indicating greater symptom severity.

Assesses depressive symptoms. Total possible score ranges from 0-27, with higher scores indicative of worse outcomes.

Assesses feelings of anxiety. Total possible score ranges from 0-21, with higher scores indicative of worse outcomes.

Assesses the severity of 16 commonly experienced PCS symptoms. Participants are instructed to rate the extent to which they have suffered from each of the listed symptoms in the past 24 hours, as compared to pre-injury levels, using a scale of 0 ("not experienced at all") to 4 ("a severe problem"). The RPQ has been demonstrated as a valid measure of PPCS with a minimal clinically important difference (MCID) of 4.5 points. It is advised to analyze this assessment as two separate scales (RPQ-13 and RRQ-3). The RPQ-3 has a total possible score of 0-12, with higher scores indicative of worse outcomes. The RPQ-13 has a total possible score of 0-52, with higher scores indicative of worse outcomes. Using these sub-scales, the instrument has good test-retest reliability and external construct validity. This questionnaire probes the separate cognitive, emotional and somatic components of PPCS.

Assesses outcomes following brain injury. Scores range from 1 to 8 with higher scores meaning better outcomes.

A self-reported 6-item questionnaire to identify and quantify changes in sleep in response to concussion and monitor these changes over time.

A 14-item self-report tool that measures sexual desire, distinguishing between dyadic (with others) and solitary (by oneself) desire. This provides insight into sexual motivation, and any changes over time.

A brief self-report tool that measures frequency of mild, moderate, and strenuous physical activity during free time in a typical week, and how this has changed following injury.

A 10-item self-report questionnaire that assesses affective, behavioral, and cognitive aspects of body image perception.

An 8-item self-report questionnaire that assesses daytime sleepiness by rating the likelihood of dozing in common daily situations, producing a total score where higher values indicate greater levels of daytime sleepiness.

A 10-item self-report questionnaire that evaluates the degree to which individuals perceive their lives as unpredictable, uncontrollable, and overwhelming over the past month. Respondents rate how often they experienced specific thoughts and feelings on a 5-point Likert scale (0 = never to 4 = very often), with total scores ranging from 0 to 40, where higher scores indicate greater perceived stress.

Waist circumference will be measured using a flexible measuring tape placed midway between the last rib and the top of the iliac crest, with the participant standing comfortably. The measurement will be recorded to the nearest 0.1 cm.

Hand grip strength will be assessed using a hand grip dynamometer. Participants will complete three trials with each hand, and the average of the three trials for each hand will be calculated and used for analysis.

At the time of the GST or initial endocrinology appointment, all participants will be asked to wear a wrist-based actigraph on their non-dominant hand (MotionWatch8, CamNtech), an accelerometer that tracks movement and activity, for six consecutive days and nights after the GST has been completed. During each actigraphy recording period, participants will complete a brief daily digital sleep diary. This will allow for objective measurement of sleep patterns, duration, and rest-activity cycles, which will be compared with participants' subjective perceptions of sleep recorded in the sleep diary.

A subset of participants will be invited to complete a two-night at-home sleep study using a portable polysomnography device (Nox SAS Solution, Nox Medical, Reykjavik, Iceland). The Nox device records multiple sleep-related physiological signals during sleep, including breathing patterns, oxygen saturation, heart rate, body position, and movement. Participants will be provided with video and written instructions to guide them through the self-setup of the device and sensors prior to the recording period. The sleep study will be completed in the participant's home over two consecutive nights. Data collected from the Nox system will be used to characterize objective sleep patterns and identify potential sleep disturbances. Approximately 30 participants will be recruited for this exploratory component, including: 10 healthy controls with no history of concussion or traumatic brain injury, 10 participants with persisting symptoms following mTBI without GHD, 10 participants with GHD & mTBI