Table 50Summary of included studies

StudyRegister / Data sourceDatesParticipantsPrevalence: overall results and results by age group - % (n/N)Definitions of complication and measurement toolsQuality of the study
Data request to UK CF registryUK CF registry20153383 people with cystic fibrosis aged 2 to 16 years
  • Age 2–11:
  • BMIp < 25th: 17.3% (432/2498)
  • BMIp>91st: 10.1% (253/2498)
  • Age 12–16:
  • BMIp < 25th: 27.5% (243/885)
  • BMIp>91st: 5.9% (52/885)
Age 2–16:
  • BMIp < 25th: 20.0% (675/3383)
  • BMIp>91st: 9.0% (305/3383)
Cystic fibrosis care teams at every specialist centre and clinic across the UK entered data on weight, height and BMI for the registry.
The following cut-offs were used:
Requires additional nutritional support:
  • <25th BMIp
  • Overweight:
  • > 91st BMIp
Moderate
  • Details on the people in the registry and on how data is collected for the registry are available in the UK CF Registry 2015 Annual Data Report and on the CF Trust website. However it is unclear from these sources if weight and height were measured using objective, standard criteria or reliably.
Heltshe 2014
United States
Retrospective study		US CF Foundation National RegistryJanuary 2004–December 20091992 infants and children with cystic fibrosis
Age: 0 to 24 months		Age 12 months (N=374):
  • weight for age <10th: 11%
  • weight for age <5th: 8.3%
  • weight for age <2.5th: 3.7%
  • weight velocity (GUO-US) <50th: 48.1%
  • weight velocity (WHO)<50th: 30.5%
  • weight velocity <10th (WHO): 6.4%
  • weight velocity<5th (WHO): 4.5%
  • weight velocity<2.5th (WHO): 3.5%
  • length for age <10th: 26.8%
  • length for age <5th: 17.7%
  • length for age <2.5th: 10.4%
  • length velocity (GUO-US) <50th: 45.7%
  • length velocity <50th (WHO): 38.4%
  • length velocity <10th (WHO): 20.7%
  • length velocity<5th (WHO): 13.4%
  • length velocity<2.5th (WHO): 13.4%
Age 24 months (N=317):
  • weight for age <10th: 6.9%
  • weight for age <5th: 2.8%
  • weight for age <2.5th: 1.9%
  • weight velocity (GUO-US) <50th: 59.3%
  • weight velocity (WHO)<50th: 51.1%
  • weight velocity <10th (WHO): 18.3%
  • weight velocity<5th (WHO): 12.6%
  • weight velocity<2.5th (WHO): 8.2%
  • length for age <10th: 24.9%
  • length for age <5th: 17%
  • length for age <2.5th: 11.4%
  • length velocity (GUO-US) <50th: 57.4%
  • length velocity <50th (WHO): 58.7%
  • length velocity <10th (WHO): 30.3%
  • length velocity<5th (WHO): 24.3%
  • length velocity<2.5th (WHO): 19.9%
Thresholds:
  • WHO standardized 2.5th, 5th, and 10th percentiles for weight and length for age
  • Guo et. al. US (Guo-US) 50th percentile for weight velocity and length velocity (as recommended by the CFF infant care guidelines)
  • WHO standardized 2.5th, 5th, 10th, and 50th percentiles for weight and length velocity
Moderate.
  • Numerators are not provided
Lai 2008
United States
Retrospective cross-sectional study		US CF Foundation Patient Registry200214702 people with cystic fibrosis
Age: <20 years		2002 CFF definition of underweight (Height percentile<5th or BMIp<10th or % Ideal Body Weight<90): 33.0%
Corrected classification of underweight ((Height percentile <5th or BMIp<10th): 26.8% BMIp<50th: 56.8%		2002 CFF definition:
  • Age <2 y old: Height percentile <5th, % Ideal Body Weight <90%, or weight for height percentile <10th.
  • Ages 2–20 y: Height percentile <5th, % Ideal Body Weight <90%, or BMIp <10th
  • Corrected classification: elimination of % Ideal Body Weight <90% as an indicator of underweight
Below BMI goal:
  • Age<2 y old: Weight for height percentile <50th.
  • Ages 2–20 y old: BMIp <50th.
Very low
  • Unclear why different definitions for infants were not taken into account in the results
  • Unclear how many infants, children, young people and adults
  • Results not disaggregated by age subgroup
  • Unclear if weight and height were measured consistently
Lucidi 2009
Italy
Prospective cross-sectional study		Multicentre study – 10 Italian CF centresJanuary 2005–December 2006892 people with cystic fibrosis
Age range: 1 month to 18 years
Mean age: 9.2		0–2 years (Height for age percentile: n=104; Weight for length percentile: n=101):
Height for age percentile<5th: 15.4%
Height for age percentile 5th–25th: 18.3%
Weight for length percentile<10th: 12.9%
Weight for length percentile 10th–25th: 22.7% 2–18 years (n=788):
Height for age percentile <5th: 11.8%
Height for age percentile 5th–25th: 29.3%
BMIp<15th: 20.9%
BMIp 15th–25th: 9.6%
BMIp<50th: 54.4%
10–14 years (n=179):
Height for age percentile<5th: 11.7%
BMIp<15th: 20.1%
14–18 years (n=183):
Height for age percentile <5th: 21.9%
BMIp<15th: 27.9%
0–18 years (n=892):
Height for age percentile <5th: 12.2%
Height for age percentile 5th–25th: 28%		Nutritional failure was defined as Height for age percentile <5th (all ages), Weight for length percentile <10th (<2 years), BMIp<15th (2–18 years)
Risk of malnutrition: Height for age percentile 5th25th (all ages), Weight for length percentile 10th–25th (<2 years), BMIp
15th–25th (2–18 years)
Height and weight were measured (when the patient was in a stable clinical condition) by specifically trained personnel.
Reproducibility in anthropometric measurement was evaluated by comparing measures obtained with standard instruments in all centres with those obtained with reference instruments in a sample of patients.		Moderate:
  • No numerators
  • Some age subgroups included less than 250 people
Zhang 2010
United States
Retrospective study		CFF Patient Registry1986–20053306 people with cystic fibrosis
Age: 2 to 18.5 years
  • Unadjusted height percentile <5th: 16%
  • Unadjusted height percentile <10th: 26%
  • Himes adjusted height percentile <5th: 18%
  • Himes adjusted height percentile: <10th: 31%
  • CFF lower bound method: 24%
Procedure to calculate CFF target height and range (lower bound method):
1. Average 2 parental heights to obtain mid-parental height. Calculate the child’s target adult height by adding 6.5 cm to mid-parental height for a boy, or subtracting 6.5 cm for a girl. Apply ±10 cm for a boy or ±9 cm for a girl to define the target height range.
2. Plot target height and range at age 20 years on the 2000 CDC growth chart and estimate their respective percentiles.
3. Extrapolate the percentiles of target height and range at age 20 to the child’s current age.
4. Plot the child’s height on the 2000 CDC growth chart; if his/her height percentile is below the target height lower bound, he/she is considered to be below genetic potential.
Procedure to calculate Himes adjusted height
1. Calculate mid-parental height.
2. Based on the child’s sex, age, height and mid-parent height, find the adjustment value from the reference tables.
3. Apply the adjustment value to the child’s height to obtain adjusted height.
4. Plot adjusted height on the 2000 CDC growth chart to obtain adjusted height percentile.		Moderate
  • Self-reported parental heights
Zhang 2013
Unites States
Retrospective study		US CF Foundation RegistryPHV was calculated in relation to time interval 1994–2008.
Registry records from 1986–2008 were used to identify participants.		1862 people with cystic fibrosis born in 1984–87.
Age: 10 to 18 years.		Pubertal peak height velocity (PHV)
  • Normal: 60.3% (1123/1862)
  • Delayed: 9.4% (175/1862)
  • Attenuated: 20.8% (387/1862)
  • Delayed and attenuated: 5.3% (98/1862)
  • Unknown: 4.2% (79/1862)
Longitudinal standard for peak height velocity for North American children developed by Tanner and Davies were used to define normal PHV. PHV was classified either as normal, delayed (PHV age at 2 SD later than average), attenuated (magnitude<5th percentile), or both delayed and attenuated.High

Abbreviations: BMIp: BMI percentile; BMI: Body Mass Index; CDC: Centre for Disease Control and Prevention; CF: Cystic Fibrosis; CFF: Cystic Fibrosis Foundation; PHV: Peak Height Velocity; WHO: World Health Organization

From: 8, Complications of cystic fibrosis

Cover of Cystic Fibrosis
Cystic Fibrosis: Diagnosis and management.
NICE Guideline, No. 78.
National Guideline Alliance (UK).
Copyright © NICE 2017.

NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health.