The four week time frame for somatic symptom questionnaires reflects subjective symptom burden best

OBJECTIVE

Various questionnaires are available to assess somatic symptom burden, however their assessment time frames vary largely. The aim of this study was to investigate the most relevant assessment time frame for somatic symptoms by relating somatic symptom burden, with varying time frames, to quality of life (QoL) and health anxiety as indicators for clinical relevance of symptoms.

METHODS

This study was performed in data derived from a convenience sample of 3477 participants (age: 48.0 (SD 14.1), 66.4% female) of the Dutch research platform HowNutsAreTheDutch. Symptom burden was assessed using all items from the Patient Health Questionnaire-15 (PHQ-15) and 6 items of the Symptom Checklist-90 SOM (SCL-90 SOM). Five versions of the questionnaire were constructed, which evaluated symptom burden during the past 24h, 1week, 2weeks, 4weeks, and 3months.

RESULTS

Symptom burden significantly increased with each step increase in time frame until 4weeks, with no further increase when comparing 4weeks and 3months. The time frame of 4weeks provided the strongest associations between somatic symptom burden and health anxiety (B=1.635; 95%CI: 1.368 to 1.938; p≤0.001). This was also true when analysing the association between QoL and the symptom groups of musculoskeletal (B=-1.54; 95%CI: -1.93 to -1.16;p≤0.001) and gastrointestinal symptoms (B=-0.71; 95%CI: -0.96 to -0.47;p≤0.001).

CONCLUSION

An assessment time frame of 4weeks for somatic symptom questionnaires reflects clinically relevant somatic symptom burden in terms of QoL and health anxiety best, followed by the 3months' time frame.

Measuring BDNF in saliva using commercial ELISA: Results from a small pilot study

Brain-derived neurotrophic factor (BDNF) is a protein often studied in psychiatric populations. Commercial ELISA kits have been validated for measuring BDNF in blood plasma and serum, but blood collection is an invasive method which cannot always be used. The aim of this pilot study was to explore the noninvasive alternative of measuring BDNF in saliva. Three different commercial ELISA kits were used to analyze parallel plasma and saliva samples from six healthy adults. In total 33 plasma and 33 saliva samples were analyzed according to manufacturers' standard protocols. BDNF was successfully measured in plasma in two of the three kits, of which the results correlated highly (r_s =.88). BDNF could not be measured reliably in saliva. The results of this pilot study suggest that techniques of commercial BDNF kits may not be ready for noninvasive saliva measurements, which limits the sampling frequency and settings.

The relationship between 63days of 24-h urinary free cortisol and hair cortisol levels in 10 healthy individuals

BACKGROUND

Interest in measuring cortisol in scalp hair is increasing because of its assumed ability to provide a historical timeline of previous systemic levels of cortisol. Yet, it remains uncertain how well hair cortisol represents the total systemic secretion of cortisol over time.

METHODS

Ten healthy individuals collected 24-h urine samples for 63 consecutive days and provided a hair sample at the end of the study period. 24-h urinary creatinine levels in every urine sample were determined to assess completeness of the samples. Cortisol levels in 24-h urine samples and in hair were measured with liquid chromatography tandem mass spectrometry. The correlations between urinary cortisol and hair cortisol were calculated using Kendall's tau.

RESULTS

We found a nonsignificant moderate correlation between average urinary cortisol secretion and average hair cortisol concentration r_т=0.422, p=0.089.

CONCLUSIONS

Hair cortisol concentration correlates low to moderately with 24-h urinary cortisol concentration over a period of 63days.

HowNutsAreTheDutch (HoeGekIsNL): A crowdsourcing study of mental symptoms and strengths

HowNutsAreTheDutch (Dutch: HoeGekIsNL) is a national crowdsourcing study designed to investigate multiple continuous mental health dimensions in a sample from the general population (n = 12,503). Its main objective is to create an empirically based representation of mental strengths and vulnerabilities, accounting for (i) dimensionality and heterogeneity, (ii) interactivity between symptoms and strengths, and (iii) intra-individual variability. To do so, HowNutsAreTheDutch (HND) makes use of an internet platform that allows participants to (a) compare themselves to other participants via cross-sectional questionnaires and (b) to monitor themselves three times a day for 30 days with an intensive longitudinal diary study via their smartphone. These data enable for personalized feedback to participants, a study of profiles of mental strengths and weaknesses, and zooming into the fine-grained level of dynamic relationships between variables over time. Measuring both psychiatric symptomatology and mental strengths and resources enables for an investigation of their interactions, which may underlie the wide variety of observed mental states in the population. The present paper describes the applied methods and technology, and presents the sample characteristics. Copyright © 2015 John Wiley & Sons, Ltd.