Evaluating and optimizing bone health in children with chronic health conditions

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BACKGROUND   

Paediatric health care providers (HCPs) play an important role in optimizing bone health. Childhood accrual of bone mass accelerates in adolescence, with peak lifetime bone mass typically achieved between 20 and 25 years of age ^[1]-[3]. Thus, addressing modifiable risk factors throughout childhood is essential. Critical factors include a healthy lifestyle, adequate vitamin D and calcium intake, good health, and normally timed puberty. Conversely, chronic health conditions can create multiple risks for blunted bone accrual and reduced adult bone mass, increasing lifelong risk of fractures ^[2][3]. This practice point reviews a targeted approach to evaluating bone health, focusing on modifiable factors, and provides management recommendations. Primary osteoporosis, such as osteogenesis imperfecta, requires specialist care that is beyond the scope of this practice point.

RISK FACTORS FOR REDUCED BONE MASS

Recognition of risk factors for reduced bone mass is an essential step toward promoting bone mass accrual (Table 1) ^[1][4]-[12].

HISTORY

A targeted history explores risk factors (Table 1) and elicits personal and family fracture history, including the number of fractures, location, and etiology. Inquire about back pain, which could be a symptom of a vertebral fracture ^[13][14]. Table 2 defines paediatric osteoporosis, which must be considered in any child with low-energy or multiple fractures. Low-energy fractures are associated with a fall from standing height or lower ^[15].  

The next step is to review diet and lifestyle, using validated tools (Table 3). Consider sharing parent notes ^[17] from the Canadian Paediatric Society’s CaringforKids website to start conversations with families about calcium and vitamin D intake, physical activity, sun exposure, and use of sunscreen. Note that in Table 3, the Dietary Reference Intakes (DRIs) are population-based, while the Recommended Dietary Allowance (RDA) is an individual’s usual Intake Goal ^[18]. The Tolerable Upper Intake Level (UL) is defined as the highest average daily intake that likely poses no risk of adverse health effects for almost all individuals. Moreover, consumption of caffeine, carbonated beverages, cigarettes, and alcohol should be reviewed, as all are associated with reduced bone mass ^[19].

Sun protection (e.g., sunscreen use and sun avoidance) is important for reducing skin cancer risk ^[20]. Although most Canadians have replete vitamin D status during the synthesizing months (April to October), a sunscreen with an SPF >8 reduces cutaneous vitamin D synthesis ^{[19][21]-[23]}.

Also, review the onset of puberty and its completion, and take a detailed menstrual history. Sex hormones play a critical role in bone mass accrual, and even physiologically delayed puberty contributes to symptomatic, adult-onset osteoporosis ^[24].

Lastly, review the use of osteotoxic medications (Table 4). Glucocorticoids are most commonly associated with increased susceptibility to fragility fractures, particularly vertebral fractures, which are often asymptomatic ^[13][14]. The dose, duration, and route of glucocorticoids that increase fracture risk are not clear. Despite the risk for bone harm posed by some osteotoxic medications, control of the underlying disease can improve bone mass over the longer term compared to inadequately treated disorders ^[5].

PHYSICAL EXAMINATION

Growth charts provide important information regarding pubertal and nutritional status. A pubertal growth spurt denotes the presence of sex hormones. Both an under-  and overweight body mass index are risk factors for reduced bone mass ^[29]. In children younger than 7 years, other signs of nutritional deficiency should be sought, such as rachitic signs, with widened metaphyses, limb pain, or deformities (e.g., genu valgus or varum). A clinical assessment for vertebral fracture is performed  by asking the child to localize any pain and palpating thoracic and lumbar vertebrae for tenderness ^[13][14][30].

Pubertal assessment includes Tanner staging for breast development in girls (onset 10 years – range 6.5 to 13 years) or testicular enlargement in boys (11 to 12 years  – range 9 to 14 years) ^[31].

Finally, a physical examination can detect less common findings suggestive of primary osteoporosis (e.g., blue gray sclera in osteogenesis imperfecta or joint laxity in collagen disorders, such as Ehlers-Danlos syndromes) ^[4][32].

POTENTIAL INVESTIGATIONS

Without a diagnosis of primary or paediatric osteoporosis (Table 2), most children do not require any investigations ^[16]. Obtaining a 25-hydroxyvitamin D (25-OH-D) measurement is typically indicated only when evaluating rickets or recurrent low-trauma fractures, although additional bone-specific investigations may be warranted after discussion with a bone health expert. Opinions differ in the absence of strong evidence for other testing indications for 25-OH-D ^[19][23][33]. An expert committee of the National Academies of Sciences, Engineering, and Medicine (NASEM) concluded in 2011 that almost all people are sufficient at levels ≥50 nmol/L ^[23]. Because 25-OH-D is a negative acute phase reactant, its suppression with acute illness limits its utility ^[34].

According to the 2019 International Society for Clinical Densitometry (ISCD) guidelines, a dual-energy X-ray absorptiometry (DXA) scan may be indicated when a child is being considered for an intervention to decrease fracture risk (e.g., bisphosphonate treatment) because imaging may influence follow-up and management (Table 5) ^[16]. DXA locations are posterior-anterior spine and total body (less head), bone mineral content (BMC) and BMD. Results from individuals with short stature need adjustment for height based on appropriate reference data ^[16]. Alternative sites are used for children with mobility issues ^[16].

OFFICE INITIATIVES                                                                                                 

Encouraging families to be aware of and meet RDAs for calcium and vitamin D through their regular diet is more likely to ensure long-term adherence than prescribing supplements ^[19][23]. Supplementation may be required at times to ensure adequate intake or to manage vitamin D deficiency ^{[19][23][33][39]}. Consensus guidelines suggest that a supplement of 2000 international units (IU) per day of vitamin D for 3 months treats deficiency, though the data remain controversial ^[19][40][41]. Long-term intakes of calcium or vitamin D above the UL increase the risk of adverse health effects, including nephrolithiasis, hypercalcemia, and cardiovascular events, without enhancing bone mass ^[42]-[46]. Individuals with specific dietary requirements (e.g., due to a restrictive diet or malabsorption disorders), or whose diet is limited by poverty may need targeted guidance or specialized advice from a dietitian ^[47].

Encouraging child and family participation in weight-bearing activities such as daily walks can activate the muscle-bone units  and augment bone mass ^[48]-[51]. Recommending  a standing frame for the non-ambulatory child or passive physical movement for infants born prematurely may help mitigate bone loss, although evidence for both practices is mixed ^[52][53].

Some institutions use bone health algorithms to identify children at high risk for fractures. Special fragility stickers on hospital charts and posters at the bedside can alert HCPs to the need for extra care during procedures, such as bed transfer or phlebotomy ^[54][55].

BONE HEALTH TEAM AND PHARMACOTHERAPY

A child who meets ISCD criteria for paediatric osteoporosis or who is suspected to have primary osteoporosis should be referred to a bone health expert, typically a paediatric endocrinologist ^[4][16]. Specialized assessments such as a DNA analysis may be required, as may bone anti-resorption drugs ^[56][57] or sex steroid replacement. For youth with anorexia nervosa, the mainstays of therapy remain psychotherapy and nutritional rehabilitation, which should restore menses. Sex steroid use does not address the underlying causes of amenorrhea ^[58]-[60].

KEY POINTS FOR PRACTICE

• Essential office initiatives include the early identification of problems and anticipatory guidance on diet, exercise, and puberty using helpful tools developed by the CPS (e.g., Healthy Bones in Children and Youth, Healthy Active Living, and Sun Safety) ^[17][20][50].
• Few children need laboratory investigations, though a conversation with a bone health expert may guide specific investigations. Formal consultation is essential for children with evidence of osteoporosis.

Acknowledgements

This practice point has been reviewed by the Adolescent Health and Nutrition and Gastroenterology Committees of the Canadian Paediatric Society.

CANADIAN PAEDIATRIC SOCIETY COMMUNITY PAEDIATRICS COMMITTEE (2020-2021)

Members: Tara Chobotuk MD, Carl Cummings MD (past Chair), Michael Hill MD, Audrey Lafontaine MD, Alisa Lipson MD, Marianne McKenna MD (Board Representative), Julia Orkin MD (Chair)

Liaison: Peter Wong MD (CPS Community Paediatrics Section)

Principal authors: Celia Rodd MD, Nicole Kirouac RN, BN, Julia Orkin MD, Ruth Grimes MD

References

Disclaimer: The recommendations in this position statement do not indicate an exclusive course of treatment or procedure to be followed. Variations, taking into account individual circumstances, may be appropriate. Internet addresses are current at time of publication.