Newborn Screening for Congenital Hypothyroidism, Congenital Adrenal Hyperplasia, and Glucose-6-Phosphate Dehydrogenase Deficiency for Improving Health Care in India

Current Status of Newborn Bloodspot Screening Worldwide 2024: A Comprehensive Review of Recent Activities (2020-2023)

Newborn bloodspot screening (NBS) began in the early 1960s based on the work of Dr. Robert "Bob" Guthrie in Buffalo, NY, USA. His development of a screening test for phenylketonuria on blood absorbed onto a special filter paper and transported to a remote testing laboratory began it all. Expansion of NBS to large numbers of asymptomatic congenital conditions flourishes in many settings while it has not yet been realized in others. The need for NBS as an efficient and effective public health prevention strategy that contributes to lowered morbidity and mortality wherever it is sustained is well known in the medical field but not necessarily by political policy makers. Acknowledging the value of national NBS reports published in 2007, the authors collaborated to create a worldwide NBS update in 2015. In a continuing attempt to review the progress of NBS globally, and to move towards a more harmonized and equitable screening system, we have updated our 2015 report with information available at the beginning of 2024. Reports on sub-Saharan Africa and the Caribbean, missing in 2015, have been included. Tables popular in the previous report have been updated with an eye towards harmonized comparisons. To emphasize areas needing attention globally, we have used regional tables containing similar listings of conditions screened, numbers of screening laboratories, and time at which specimen collection is recommended. Discussions are limited to bloodspot screening.

Newborn screening for congenital hypothyroidism, congenital adrenal hyperplasia and glucose-6-phosphate dehydrogenase deficiency in Bihar: A pressing priority in today's time

Background and Objective

Newborn screening (NBS) aims towards early detection of congenital disorders or prevention of intellectual and physical defects and life-threatening illness. Three disorders namely congenital hypothyroidism (CH), congenital adrenal hyperplasia (CAH) and glucose-6-phosphate dehydrogenase deficiency (G-6-PDD) were selected for a preliminary study for NBS. The study aimed to establish NBS in the Indian scenario that could lay a framework for future such initiatives.

Methods

A screening programme was conducted at a tertiary care hospital for 1 year. All the neonates born at All India Institute of Medical Sciences (AIIMS), Patna, were screened for their blood levels of glucose-6-phosphate dehydrogenase (G-6-PD), 17-hydroxyprogesterone (17-OHP) and thyroid-stimulating hormone (TSH). Heel-prick blood samples were collected within 48-72 h of birth, and the level of these parameters was accessed by enzyme immunoassay (EIA).

Results

A total of 492 neonates were born from January 2020 to December 2020, of which 369 newborns were screened for CAH, CH and G-6-PDD. Of 369 neonates, one case (male) had an increased level of TSH, six cases (all males) had an increased level of 17-OHP and no case was found with G-6-PDD.

Interpretation and Conclusions

Preliminary data on the prevalence of various genetic disorders revealed that CAH is the most prevalent disorder followed by CH in the population of Bihar. More efforts need to be undertaken to create awareness and to make screening a successful programme in India. A cost-effective nationwide screening programme is highly recommended for the detection of such cases at the earliest to avoid their future complication.

Congenital hypothyroidism in India: A systematic review and meta-analysis of prevalence, screen positivity rates, and etiology

Background

Congenital hypothyroidism (CH) is the leading cause of preventable mental retardation, which is currently not universally screened in India. Knowledge of the country-specific prevalence of the disease can guide in establishing a universal screening program.

Methods

We performed a systematic review and meta-analysis to assess the prevalence, screen positivity rates, compliance to recall and etiology of CH in India. The databases of PubMed, Embase, Google scholar and IMSEAR were searched on 1^st October 2021. All observational studies reporting at least one of the outcomes of interest were included. Two reviewers independently extracted the data and appraised the quality of studies using the Joanna Briggs tool for prevalence studies. Estimates were pooled using a random-effects model with double arcsine transformation (MetaXL software). PROSPERO database registration number was CRD42021277523.

Findings

Of the 2 073 unique articles retrieved, 70 studies were eligible for inclusion. The prevalence of CH (per 1 000 neonates screened) was 0·97 (95% confidence intervals/CI: 0·9, 1·04) in non-endemic areas (54 studies and 819 559 neonates), 79 (95% CI: 72, 86) in endemic areas (3 studies, 5 060 neonates), 50 (95% CI: 31, 72) in neonates born to mothers with thyroid disorders, and 14 (95% CI: 8, 22) in preterm neonates. At thyroid stimulation hormone cut-off of 20 mIU/L, the screen positivity rates were 5·6% (95% CI: 5·4%, 5·9%) for cord blood samples and 0·19% (95% CI: 0·18%, 0·2%) for postnatal sample. About 70% (95% CI: 70, 71) of screen positive neonates were retested with diagnostic tests. Among neonates with permanent hypothyroidism, thyroid dysgenesis 56·6% (95% CI: 50·9%, 62·2%) was more common than dyshormonogenesis 38·7% (95% CI: 33·2%, 44·3%).

Interpretation

The prevalence of congenital hypothyroidism in India is higher than global estimates. Screen positivity rate was higher for cord blood screening when compared to postnatal screening. Compliance with confirmatory testing was higher for cord blood screening.

Funding

The study was not funded by any source.

Need and Viability of Newborn Screening Programme in India: Report from a Pilot Study

India, a country with the second largest population in the world, does not have a national newborn screening programme as part of its health policy. With funding support from the Grand Challenges Canada, a pilot newborn screening programme was implemented for the Udupi district of South India to study the need and viability of a national programme in India. Six disorders were selected for the study based on the availability of funding and recommendation from pediatricians in the district. Here, we report the observed incidence during the study. A cost-effectiveness analysis of implementing newborn screening in India was performed. It is evident from our analysis that the financial loss for the nation due to these preventable diseases is much higher than the overall expenditure for screening, diagnosis, and treatment. This cost-effectiveness analysis justifies the need for a national newborn screening programme in India.

Human and Economic Cost of Disease Burden Due to Congenital Hypothyroidism in India: Too Little, but Not Too Late

BACKGROUND

Congenital hypothyroidism (CH) is one of the most common preventable causes of mental retardation. Implementing newborn screening (NBS) in >52 countries enabled early detection and to initiate treatment of neonates with CH. India is yet to implement a national NBS program even though an estimated 5-15% of sick newborns suffer from genetic and metabolic disorders. Recent pilot studies confirm that the CH incidence rates range from 1 in 500 to 1 in 3,400 live births. Our objective was to estimate overall incidence rates of congenital hypothyroidism and to evaluate the costs and benefits of implementing universal NBS for CH in India.

METHODS

We used the best available epidemiological and cost data to synthesize incidence rates and screening costs for CH in India. We conducted a meta-analysis of country-specific published literature and included 14 studies to calculate baseline CH incidence rates. We used two models to estimate intellectual disability in unscreened cohorts. Disability-adjusted life years (DALY) were calculated to quantify burden of disease utilizing disability weights. Direct costs including screening, confirmatory tests, and treatment costs were obtained from public and private market sources. Economic benefits were calculated from lost DALY using human capital approach and value of statistical life methods, utilizing gross national income (GNI) per capita data and value of statistical life year (VSLY), respectively. Cost discounting was used to estimate the present value of future benefits over lifetime of affected newborns.

RESULTS

The incidence rate of CH in India is 72 (95% CI: 58, 85) cases per 100,000 live births. Based on this data, 1 in 1,388 (95% CI: 1166, 1714) infants were diagnosed with CH in India for the year 2018. The estimated annual incidence ranged from 14,000 to 20,730 cases, and those at risk for intellectual disability ranged from 5,397 to 13,929 cases. Estimated discounted and undiscounted lost DALYs were 57,640 and 410,000, respectively. Direct annual costs for universal screening for CH in India is around USD187 million. Based on current incidence and expected severity of sequelae, economic losses ranged from USD 159 million to 1.1 billion. Benefit-cost ratios ranged from 1.8 to 6.

CONCLUSIONS

Universal NBS for CH is one of the healthcare interventions that is beneficial to prevent morbidity and cost saving. The cumulative economic benefits, derived from prevention of intellectual disability, assuming cost effectiveness threshold of three times of gross domestic product per capita, far outweigh the direct and indirect costs of screening, treatment, and surveillance throughout the life of the affected individuals. Our analysis strongly supports the argument for investing in NBS that provides good value for money and would yield substantial financial gains for the country.

CAH Newborn Screening in India: Challenges and Opportunities

Congenital adrenal hyperplasia (CAH) is a common treatable disorder which is associated with life-threatening adrenal crisis, sexual ambiguity, and/or abnormal growth if undiagnosed. Newborn screening is a cost-effective tool to detect affected babies early after birth to optimize their treatment and follow-up. Newborn screening however is in its nascent stage in India where it is not yet introduced universally for all babies. The following review briefly highlights the challenges (e.g., lack of universal screening, healthcare resources) and opportunities (e.g., reduction in morbidity and early correct gender assignment in females) associated with newborn screening for CAH in a large Indian birth cohort.