On the estimation of the effect of weight change on a health outcome using observational data, by utilising the target trial emulation framework.

BACKGROUND/OBJECTIVES: When studying the effect of weight change between two time points on a health outcome using observational data, two main problems arise initially (i) 'when is time zero?' and (ii) 'which confounders should we account for?' From the baseline date or the 1st follow-up (when the weight change can be measured)? Different methods have been previously used in the literature that carry different sources of bias and hence produce different results. METHODS: We utilised the target trial emulation framework and considered weight change as a hypothetical intervention. First, we used a simplified example from a hypothetical randomised trial where no modelling is required. Then we simulated data from an observational study where modelling is needed. We demonstrate the problems of each of these methods and suggest a strategy. INTERVENTIONS: weight loss/gain vs maintenance. RESULTS: The recommended method defines time-zero at enrolment, but adjustment for confounders (or exclusion of individuals based on levels of confounders) should be performed both at enrolment and the 1st follow-up. CONCLUSIONS: The implementation of our suggested method [adjusting for (or excluding based on) confounders measured both at baseline and the 1st follow-up] can help researchers attenuate bias by avoiding some common pitfalls. Other methods that have been widely used in the past to estimate the effect of weight change on a health outcome are more biased. However, two issues remain (i) the exposure is not well-defined as there are different ways of changing weight (however we tried to reduce this problem by excluding individuals who develop a chronic disease); and (ii) immortal time bias, which may be small if the time to first follow up is short.

Vessel wall magnetic resonance and arterial spin labelling imaging in the management of presumed inflammatory intracranial arterial vasculopathy.

Optimal criteria for diagnosing and monitoring response to treatment for infectious and inflammatory medium-large vessel intracranial vasculitis presenting with stroke are lacking. We integrated intracranial vessel wall MRI with arterial spin labelling into our routine clinical stroke pathway to detect presumed inflammatory intracranial arterial vasculopathy, and monitor disease activity, in patients with clinical stroke syndromes. We used predefined standardized radiological criteria to define vessel wall enhancement, and all imaging findings were rated blinded to clinical details. Between 2017 and 2018, stroke or transient ischaemic attack patients were first screened in our vascular radiology meeting and followed up in a dedicated specialist stroke clinic if a diagnosis of medium-large inflammatory intracranial arterial vasculopathy was radiologically confirmed. Treatment was determined and monitored by a multi-disciplinary team. In this case series, 11 patients were managed in this period from the cohort of young stroke presenters (<55 years). The median age was 36 years (interquartile range: 33,50), of which 8 of 11 (73%) were female. Two of 11 (18%) had herpes virus infection confirmed by viral nucleic acid in the cerebrospinal fluid. We showed improvement in cerebral perfusion at 1 year using an arterial spin labelling sequence in patients taking immunosuppressive therapy for >4 weeks compared with those not receiving therapy [6 (100%) versus 2 (40%) P = 0.026]. Our findings demonstrate the potential utility of vessel wall magnetic resonance with arterial spin labelling imaging in detecting and monitoring medium-large inflammatory intracranial arterial vasculopathy activity for patients presenting with stroke symptoms, limiting the need to progress to brain biopsy. Further systematic studies in unselected populations of stroke patients are needed to confirm our findings and establish the prevalence of medium-large artery wall inflammation.

Intravenous Furosemide for Acute Decompensated Congestive Heart Failure: What Is the Evidence?

Use of intravenous furosemide rather than oral administration in acute decompensated congestive cardiac failure is universally recommended in international guidelines. We argue that this recommendation is not supported by the existing evidence, and suggest that trials should be performed to determine whether larger doses of oral furosemide should be prescribed prior to an IV switch. This could reduce length of hospital admissions and allow for more patients to be managed in the primary care setting.

The role of Gardnerella vaginalis in nonspecific vaginitis in intra uterine contraceptive device users.

Two Hundred Forty patients who had Intra Uterine Contraceptive Device (IUCD) and manifested of nonspecific vaginitis were investigated for the presence of G. vaginalis. Pure growth of this organism was obtained in 14(5.8%) cases while 116(48.3%) cases showed this organism in association with other organisms e.g. Esch. coli (11.7%), Klebsiella (9.2%), Candida (9.2%), Strept. faecalis (7.3%), Proteus species (5.8%) and Staph. albus (5%).

Post-partum Copper-T insertion -- a trial.

PIP: Requiring only one-time motivation, the IUD appears to be an ideal method for spacing child births. The author reports findings from a study in which 115 women were motivated to accept the use of the Copper-T (Cu-T) IUD within the first ten days post-partum. Cases with an history of premature membrane rupture, vaginal examination outside by unqualified personnel, ante- or post-partum hemorrhage, or any intrauterine manipulation were excluded from the study. IUD insertion was conducted in the cases shortly after they had undergone child delivery at Dayanand Medical College and Hospital in Ludhiana, India. 14 subjects were teenagers, 66 were aged 20-25 years, and 35 were aged 26-30 years. 60 were para one, 37 were para two, and 18 para three. 52 had their primary IUD insertions soon after delivery, while the rest were almost evenly distributed over the first post-partum week. The women were then followed up at one week, one month, and three months intervals. At the end of three months, 67% of cases had retained the Cu-T without appreciable symptoms. In 4.3% of cases, however, the Cu-T slid into the cervical canal. The Cu-T in these cases was removed and a fresh one installed. 6.1% of cases expelled the Cu-T unnoticeably and 22.6% of cases were lost to follow-up. The author concludes that despite the high rate of expulsion, post-partum insertion of Cu-T has a role in family planning in the rural setting where some women come to the hospital only for delivery. The need to take care in selecting appropriate acceptors is stressed.^ieng

Adolescent girls' anxieties -- role of stressful life events.

PIP: The study aim was to examine stressful events among 300 adolescent girls 11-17 years old enrolled in school in India. 50.33% had illiterate mothers. 22.33% had mothers who had a primary education and 25.34% who had a secondary education. 82.33% (247) were from nuclear families, and 17.67% (53) were from joint families. The largest proportions reported financial problems (38.67%) followed by household moves (30.33%) and a close relative's death (27.33%). Other concerns reported were parental frequent change or loss of job (12.33%), involvement in a court case (4.67%), death of one or both parents (4.33%), and frequent parental arguments (1.33%) and serious family accidents (1.33%). No stressful events were reported by 31.69% (95 girls); 68.34% reported stressful family events. A significant correlation was found between anxiety and life in a nuclear family (p 0.001). Anxiety was also higher, but not statistically significantly so, among families with an illiterate mother and lower socioeconomic status. More anxieties were reported among girls with working mothers (68%) than non-working mothers (32%). A significant correlation was found between the score of life events and the number of girls reporting anxieties. Individual anxieties were reported for inadequate height (15.66%), fear of boys' teasing (12.33%), losing hair (11.60%), menstrual tensions (10.33%), weak eyesight (9.66%), pimples (9.33%), weakness (8.88%), lack of study time (5.67%), excessive weight (3.67%), dark complexion (2.66%), and bad teeth (2.00%); 55.34% reported these anxieties.^ieng

A simple approach for estimating birth weight in developing countries.

PIP: Health and nutritional status of an infant are accurately assessed with birth weight. In India, almost 30% of all births are low birth weight, which is related to a high risk of mortality and morbidity. Anthropometric measures have been found to be accurate indicators of birth weight. In this study, 483 normal singleton infants were measured at mid arm circumference and maximum thigh circumference; mid arm circumference measures were also taken from mothers. The precise position for the arm measurement was at the mid point between the tip of the acromion and the olecranon process in the left upper arm to the nearest .1 cm. Thigh measurement was just below the left gluteal fold. Measurements were taken within 48 hours of birth; information was also obtained on age, gravida, parity, and gestation. With control for gestation, there was a significant correlation between mid arm circumference, maternal arm circumference, and maximum thigh circumference. Maternal arm circumference had a predictive value of 6.54% infant mid arm circumference of 46.30%, and maximum thigh circumference of 44.0%. When all three measures are used concurrently, there is an increase in predicted value to 53.68%. With use of mid arm and maximum thigh circumference together, the predictive value is 54.6%. A correlation matrix shows the interaction of age, gestation, parity, weight, and the three anthropometric measures. The mean birth weight was 2851.5 g plus or minus 473.18 g, the mean infant mid arm circumference was 9.86 cm plus or minus 1.12 cm and the maximum thigh circumference was 16.20 cm plus or minus 1.78 cm. Maternal mid arm circumference was 25.08 cm plus or minus 2.90 cm; mother's age averaged 25.35 plus or minus 3.94 years. Gestation averaged 38.76 weeks plus or minus 1.64 weeks. Birth weights ranged from a low of 1600 g to a high of 4120 g.^ieng

Efficacy of colour coded strips for classifying birth weights.

PIP: Color-coded measuring tapes have been developed as surrogates for measuring birth weight with a scale. The tapes have been correlated with birth weight to indicate low birth weight. In this study, arm circumference and thigh circumference were measured with tapes indicating low birth weight: 7.0 to 8.5 cms for mid arm circumference and 11.5 and 14.5 cms for thigh circumferences. The area in between the numbers was color coded in yellow to indicate a birth weight of 2.0 to 2.5 kg. The area under the lowest number was coded red, and the are above the highest number was coded green. The strips were tested on 281 infants to determine the accuracy of this form of measurement. Use of strips and birth weights were recorded within 48 hours of the birth. The results indicated that 54% of the low birth weight infants were correctly identified with the mid arm circumference tapes. There were 13.88% who were recorded with low birth weight out of the 281 sampled. The tape reliably measured 90% of the normal birth weight infants. The thigh circumference tape was a better measure of low birth weight. 80% of low birth weight infants were identified with the thigh circumference tape, but only 85% of normal weights were identified. When the tapes were used concurrently, accuracy of low birth weight classification was increased to 87%, but normal weight remained much the same at 85% accuracy. It is recommended that these tapes be used in combination by traditional birth attendants and other grassroots workers to identify low birth weight infants and then refer these infants for special care.^ieng

Calf circumference as a birth weight surrogate.

PIP: There remains a need to determine low birth weight in settings such as the home, where scales are not easily available. This study examined the calf circumference at a prominent point on a semi-flexed leg with a standard measuring tape to the nearest .1 cm and birth weight to the nearest 5 g. The sample included 257 full term singleton infants. The results of the correlation coefficient analysis was r = .74, which indicates a high degree of correlation between the two measures. The mean of birth weight was 2.96 g plus or minus .41 and the mean calf circumference was 9.87 cm plus or minus 1.07. Birth weight can be calculated from calf circumference by adding .172 to the multiplication of .283 times calf circumference. The calf circumference appears to exhibit the strongest correlation with birth weight regardless of the sample. A color-coded tape had been prepared which demarcated in yellow 6.5 cm and 8.25 cm as the range equivalent to 2.0 kg and 2.5 kg low birth weight. The area below 6.5 cm was colored red and the area below 8.25 was colored green. Currently, data is being collected on the efficacy and positive predictive value of using the tapes.^ieng

Consistent accuracy of mid arm circumference and calf circumference as birth weight surrogates during first few days.

PIP: Measurement within 24 hours and then daily for 10 days after birth was made of mid arm, calf, and thigh circumference, and birth weight among infants delivered by the Dayanand Medical College and Hospital in Ludhiana, Punjab State, India. The results of the correlation procedures was that mid arm an calf circumference were highly correlated with birth weights: r = .60 and r = .76 respectively. Thigh circumference data was discarded, due to technical errors. Analysis of variance found that there were not significant differences between the values of arm and calf circumference and birth weight. This information was found useful for determining birth weight with colored strips during the first 10 days after birth. The criteria of health workers in field conditions to assess birth weight with surrogate measures were satisfied: high correlation, easy measurement, and consistently accuracy over the first few days of life. Health workers do not always see new borns in the first few days. The significance of measuring birth weight is in the determination of low birth weight and the need for special care or monitoring as a means of enhancing child survival.^ieng

Efficacy of colour coded strip based on calf circumference for detection of low birth weight babies.

PIP: In India, a color-coded strip measuring calf circumference was tested for its efficacy in detecting low birth weight (=or 2.5 kg) among 306 normal singleton newborns within 48 hours of delivery. The strip has points marked at 6.5 cm and 8.25 cm. The area in-between these points correspond to 2-2.5 kg and is colored yellow. The area before 6.5 cm is colored red and the area beyond 8.25 cm is colored green. The strip correctly identified 60.38% of low birth weight newborns. It correctly identified 98.02% of normal weight newborns. Its efficacy for classifying newborns according to birth weight was significant (p 0.001; X2 = 151.88). The strip's sensitivity rates for low birth weight and for normal birth weight were 91.43% and 92.19%, respectively. These findings show that the color-coded strip is an effective means to determine low birth weight in the absence of a weighing score or spring balance. Health workers can use it to detect low birth weight babies born at home.^ieng

Correlation of some maternal variables with birth weight.

PIP: Infant survival and birth weight are dependent on the health of the mother during pregnancy. In this study, maternal weight gain in pregnancy, prepregnancy weight, height, and body mass index (BMI) were examined in terms of their correlation with birth weight. The Dayanand Medical College and Hospital in Ludhiana, Punjab State, India, conducted the study of the pregnant women in the surrounding 10 villages. Prenatal care was provided to all pregnant women and maternal variables were grouped into the BMI for 18, 18-21, and 21. The results showed a positive correlation of birth weight with prepregnancy weight, height, and BMI. A BMI of 18, which indicated chronic dietary energy insufficiency, had a correlation of r = .43 an a low prepregnancy weight of 41.44 plus or minus 2.65 kg. Prepregnancy weight had a correlation with birth weight of r = .42; height was correlated with birth weight with a r = .23. A positive correlation was apparent for BMI of 18-21 and 21, but the correlations were statistically insignificant. The objective of any prenatal health intervention would be to assure that women have a prepregnancy weight of greater than 40 g and a BMI of 18. Weight gain was the highest among women who had the lowest prepregnancy weight, but this was still insufficient to meet the recommendations.^ieng